Distributed management of keep-alive message signaling for mobile network resource conservation and optimization

ABSTRACT

Systems and methods for distributed management of keep-alive message signaling for mobile network resource conservation and optimization are disclosed. In one aspect, embodiments of the present disclosure include a method, which may be implemented on a system, of monitoring rates of data communications with a mobile device, sending a periodic message to indicate operational state to the mobile device in response to a decrease in the rates of data communications with the mobile device, sending subsequent periodic messages to indicate operational state to the mobile device at increasing intervals between the subsequent periodic messages to decrease a number of periodic messages sent over the wireless network, and acknowledging to the mobile device that the subsequent periodic messages will be sent at increased intervals, or in a manner that conserves use of the mobile network.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication No. 61/408,858 entitled “CROSS APPLICATION TRAFFICCOORDINATION”, which was filed on Nov. 1, 2010, U.S. Provisional PatentApplication No. 61/408,839 entitled “ACTIVITY SESSION AS METHOD OFOPTIMIZING NETWORK RESOURCE USE”, which was filed on Nov. 1, 2010, U.S.Provisional Patent Application No. 61/408,829 entitled “DISTRIBUTEDPOLICY MANAGEMENT”, which was filed on Nov. 1, 2010, U.S. ProvisionalPatent Application No. 61/408,846 entitled “INTELLIGENT CACHE MANAGEMENTIN CONGESTED WIRELESS NETWORKS”, which was filed on Nov. 1, 2010, U.S.Provisional Patent Application No. 61/408,854 entitled “INTELLIGENTMANAGEMENT OF NON-CACHEABLE CONTENT IN WIRELESS NETWORKS”, which wasfiled on Nov. 1, 2010, U.S. Provisional Patent Application No.61/408,826 entitled “ONE WAY INTELLIGENT HEARTBEAT”, which was filed onNov. 1, 2010, U.S. Provisional Patent Application No. 61/408,820entitled “TRAFFIC CATEGORIZATION AND POLICY DRIVING RADIO STATE”, whichwas filed on Nov. 1, 2010, U.S. Provisional Patent Application No.61/416,020 entitled “ALIGNING BURSTS FROM SERVER TO CLIENT”, which wasfiled on Nov. 22, 2010, U.S. Provisional Patent Application No.61/416,033 entitled “POLLING INTERVAL FUNCTIONS”, which was filed onNov. 22, 2010, U.S. Provisional Patent Application No. 61/430,828entitled “DOMAIN NAME SYSTEM WITH NETWORK TRAFFIC HARMONIZATION”, whichwas filed on Jan. 7, 2011, U.S. Provisional Patent Application No.61/532,857 entitled “CACHE DEFEAT DETECTION AND CACHING OF CONTENTADDRESSED BY IDENTIFIERS INTENDED TO DEFEAT CACHE”, which was filed onSep. 9, 2011, U.S. Provisional Patent Application No. 61/533,007entitled “DISTRIBUTED CACHING IN A WIRELESS NETWORK OF CONTENT DELIVEREDFOR A MOBILE APPLICATION OVER A LONG-HELD REQUEST”, which was filed onSep. 9, 2011, and U.S. Provisional Patent Application No. 61/533,021entitled “APPLICATION AND NETWORK-BASED LONG POLL REQUEST DETECTION ANDCACHEABILITY ASSESSMENT THEREFOR”, which was filed on Sep. 9, 2011, thecontents of which are all incorporated by reference herein.

This application is related to U.S. patent application Ser. No.13/176,537 [Attorney Docket No. 76443-8107.US01] entitled “DISTRIBUTEDCACHING AND RESOURCE AND MOBILE NETWORK TRAFFIC MANAGEMENT,” which wasfiled on Jul. 5, 2011, the contents of which are herein incorporated byreference.

This application is related to U.S. patent application Ser. No.13/274,265 [Attorney Docket No. 76443-8134.US01] entitled “CachingAdapted For Mobile Application Behavior and Network Conditions”, whichwas filed on Oct. 14, 2011, the contents of which are hereinincorporated by reference.

This application is related to U.S. patent application Ser. No.13/274,501 [Attorney Docket No. 76443-8134.US02] entitled “Request andResponse Characteristics based Adaptation of Distributed Caching In AMobile Network”, which was filed on Oct. 17, 2011, the contents of whichare herein incorporated by reference.

This application is related to U.S. patent application Ser. No.13/274,250 [Attorney Docket No. 76443-8138.US01] entitled “DistributedCaching In A Wireless Network Of Content Delivered For A MobileApplication Over A Long-Held Request”, which was filed on Oct. 14, 2011,the contents of which are herein incorporated by reference.

This application is related to U.S. patent application Ser. No.13/274,248 [Attorney Docket No. 76443-8139.US01] entitled “APPLICATIONAND NETWORK-BASED LONG POLL REQUEST DETECTION AND CACHEABILITYASSESSMENT THEREFOR”, which was filed on Oct. 14, 2011, and the contentsof which are herein incorporated by reference.

This application is related to U.S. patent application Ser. No. ______[Attorney Docket No. 76443-8108.US02] entitled “Cache Defeat Detectionand Caching of Content Addressed by Identifiers Intended to DefeatCache,” which is concurrently filed herewith, and the contents of whichare herein incorporated by reference.

This application is related to U.S. patent application Ser. No. ______[Attorney Docket No. 76443-8108.US03] entitled “Distributed System forCache Defeat Detection and Caching of Content Addressed by IdentifiersIntended to Defeat Cache,” which is concurrently filed herewith, and thecontents of which are herein incorporated by reference.

This application is related to U.S. patent application Ser. No. ______[Attorney Docket No. 76443-8110.US01] entitled “Mobile TrafficCategorization and Policy for Network Use Optimization,” which isconcurrently filed herewith, and the contents of which are hereinincorporated by reference.

BACKGROUND

Heartbeat messages and other forms of connection keep-alive mechanismcan be used, sent and/or implied from messages or indicators sentbetween entities, clients, and/or servers in a network to infer ordetermine the operational state of one or more endpoints of theheartbeat messages. In general, when these messages arrive and/or arereceived on-time, one entity can assume that the other is functional(i.e., healthy, operational, operating within certain known orpredictable parameters, etc.). However, when attempting to conserve theuse of a radio channel in mobile networks (e.g., to increase mobiledevice battery life, reduce congestion or signaling, etc.), heartbeatmessages, when used, may have negative impacts on system performance andbandwidth utilization. Specifically, when used by multiple applicationswithout applying any intelligence, the radio channel may be activatedtoo frequently, significantly affecting performance of the networks inparticular, since state of the art cellular networks are not designedfor connections that require frequent, low-throughput and/or smallamounts of data, including keep-alive or heart beat messages.

Each transaction puts the mobile device radio in a high-power mode for aconsiderable length of time—typically between 15-30 seconds. As thehigh-power mode can consume as much as 100× the power as an idle mode,these network-initiated applications quickly drain battery. Even if thekeep-alive messages are sent using alternative channels such as SMS, itcould also result in too many expensive (to either the operator or theuser) messages that become system overhead. The problem with constantpolling and signaling is that mobile phones also rely on signaling tosend and receive calls and SMS messages and sometimes these basic mobilephone functions are forced to take a backseat to unruly applications andother mobile clients.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates an example diagram of a system where a host serverfacilitates management of traffic, content caching, and/or resourceconservation between mobile devices (e.g., wireless devices) and anapplication server or content provider in a wireless network (orbroadband network) for resource conservation.

FIG. 1B illustrates an example diagram of a proxy and cache systemdistributed between the host server and device which facilitates networktraffic management between a device and an application server/contentprovider for resource conservation and content caching.

FIG. 2A depicts a block diagram illustrating an example of client-sidecomponents in a distributed proxy and cache system residing on a mobiledevice (e.g., wireless device) that manages traffic in a wirelessnetwork (or broadband network) for resource conservation, contentcaching, and/or traffic management.

FIG. 2B depicts a block diagram illustrating a further example ofcomponents in the cache system shown in the example of FIG. 2A which iscapable of caching and adapting caching strategies for mobileapplication behavior and/or network conditions. Components capable ofdetecting long poll requests and managing caching of long polls are alsoillustrated.

FIG. 2C depicts a block diagram illustrating additional components inthe application behavior detector and the caching policy manager in thecache system shown in the example of FIG. 2A which is further capable ofdetecting cache defeat and perform caching of content addressed byidentifiers intended to defeat cache, and can further include or becoupled to components (e.g., heartbeat manager 267) for managingkeep-alive messages.

FIG. 3A depicts a block diagram illustrating an example of server-sidecomponents in a distributed proxy and cache system that manages trafficin a wireless network (or broadband network) for resource conservation,content caching, and/or traffic management.

FIG. 3B depicts a block diagram illustrating a further example ofcomponents in the caching policy manager in the cache system shown inthe example of FIG. 3A which is capable of caching and adapting cachingstrategies for mobile application behavior and/or network conditions.Components capable of detecting long poll requests and managing cachingof long polls are also illustrated.

FIG. 3C depicts a block diagram illustrating another example ofcomponents in the proxy system shown in the example of FIG. 3A which isfurther capable of managing and detecting cache defeating mechanisms andmonitoring content sources, and can further include or be coupled tocomponents (e.g., heartbeat manager 398) for managing the timing and/orgeneration of keep-alive messages.

FIG. 4 depicts a timing diagram showing how data requests from a mobiledevice (e.g., any wireless device) to an application server/contentprovider in a wireless network (or broadband network) can be coordinatedby a distributed proxy system in a manner such that network and batteryresources are conserved through using content caching and monitoringperformed by the distributed proxy system.

FIG. 5 depicts a diagram showing one example process for implementing ahybrid IP and SMS power saving mode on a mobile device (e.g., anywireless device) using a distributed proxy and cache system (e.g., suchas the distributed system shown in the example of FIG. 1B).

FIG. 6 depicts a flow diagram illustrating an example process fordistributed content caching between a mobile device (e.g., any wirelessdevice) and remote proxy and the distributed management of contentcaching.

FIG. 7 depicts an interaction diagram showing cache management by adistributed proxy system of content delivered to a mobile applicationover a long-held request while ensuring freshness of content delivered.The optional incorporation of keep-alive message management and timingwith cache management for long-held type HTTP requests are alsoillustrated.

FIG. 8 depicts a timing diagram showing hunting mode behavior in a longpoll request and a timing diagram showing timing characteristics whenthe long poll has settled.

FIG. 9 depicts an interaction diagram showing how polls having datarequests from a mobile device (e.g., any wireless device) to anapplication server/content provider over a wireless network (orbroadband network) can be can be cached on the local proxy and managedby the distributed caching system. The optional incorporation ofkeep-alive message management and timing with cache management for HTTPrequests are also illustrated.

FIG. 10 depicts an interaction diagram showing how polls for contentfrom an application server/content provider which employscache-defeating mechanisms in identifiers (e.g., identifiers intended todefeat caching) over a wireless network (or broadband network) can bedetected and locally cached. The optional incorporation of keep-alivemessage management and timing with cache management for HTTP requestsare also illustrated.

FIG. 11 depicts a flow chart illustrating an example process forcollecting information about a request and the associated response toidentify cacheability and caching the response.

FIG. 12 depicts a flow chart illustrating an example process showingdecision flows to determine whether a response to a request can becached.

FIG. 13 depicts a flow chart illustrating an example process fordetermining potential for cacheability based on request periodicityand/or response repeatability.

FIG. 14 depicts a flow chart illustrating an example process fordynamically adjusting caching parameters for a given request or client.

FIG. 15 depicts a flow diagram illustrating an example process for usingrequest intervals to determine and to set a polling interval or rate atwhich a proxy server is to monitor an application server/content host onbehalf of the mobile device (e.g., any wireless device).

FIG. 16 depicts example timing diagrams showing timing characteristicsfor various types of request-response sequences.

FIG. 17A depicts an example of a timing diagram showing timingcharacteristics for request-response sequences.

FIG. 17B depicts an example of a timing diagram showing timingcharacteristics for request-response sequences characteristic of a longpoll.

FIG. 18 depicts a data timing diagram showing an example of detection ofperiodic request which may be suitable for caching.

FIG. 19 depicts a data timing diagram showing an example of detection ofchange in request intervals and updating of server polling rate inresponse thereto.

FIG. 20 depicts a data timing diagram showing an example of servingforeground requests with cached entries.

FIG. 21 depicts a data timing diagram showing an example of the possibleeffect of cache invalidation that occurs after outdated content has beenserved once again to a requesting application.

FIG. 22 depicts a data timing diagram showing cache management andresponse taking into account the time-to-live (TTL) set for cacheentries.

FIG. 23 depicts a diagram of an example of the component API layer forthe cache store.

FIG. 24 depicts a diagram showing one example of the data model for thecache store.

FIG. 25 depicts a conceptual diagram of one example of the data model ofa cache entry in the cache store.

FIG. 26A-B depicts example request-response pairs showing cacheableresponses addressed by identifiers with changing parameters.

FIG. 27 depicts a diagram showing various options for batching thesending of keep-alive messages and/or related indicators with othermessages in a mobile network and/or in a distributed caching system.

FIG. 28 depicts an example of a timing diagram showing timing ofkeep-alive messages in response to changes in polling intervals.

FIG. 29 depicts a flow chart illustrating an example process fordynamically adapting the use of keep-alive messaging and/or timingthere-between based on rates of data communications of a mobile device(wireless device).

FIG. 30 depicts a flow chart illustrating an example process forbatching keep-alive messages sent to a mobile client or wireless deviceand decreasing the number of keep-alive messages that are sent.

FIG. 31 depicts a flow chart illustrating an example process forcomputing timing intervals between keep-alive messages based on rate ofcommunication at a mobile client or wireless device.

FIG. 32 depicts a flow chart illustrating an example process for usingan initial value for a time interval between keep-alive messages andadjusting the initial value based on subsequent rates of communicationsbetween a mobile device and a proxy server.

FIG. 33 depicts a flow chart illustrating an example process fordecreasing the number of periodic messages needed to indicate healthfulstatus of network components and intelligently acknowledging mobileclients of the decreasing timing intervals.

FIG. 34 shows a diagrammatic representation of a machine in the exampleform of a computer system within which a set of instructions, forcausing the machine to perform any one or more of the methodologiesdiscussed herein, may be executed.

DETAILED DESCRIPTION

The following description and drawings are illustrative and are not tobe construed as limiting. Numerous specific details are described toprovide a thorough understanding of the disclosure. However, in certaininstances, well-known or conventional details are not described in orderto avoid obscuring the description. References to “one embodiment” or“an embodiment” in the present disclosure can be, but not necessarilyare, references to the same embodiment and such references mean at leastone of the embodiments.

Reference in this specification to “one embodiment” or “an embodiment”means that a particular feature, structure, or characteristic describedin connection with the embodiment is included in at least one embodimentof the disclosure. The appearances of the phrase “in one embodiment” invarious places in the specification are not necessarily all referring tothe same embodiment, nor are separate or alternative embodimentsmutually exclusive of other embodiments. Moreover, various features aredescribed which may be exhibited by some embodiments and not by others.Similarly, various requirements are described which may be requirementsfor some embodiments but not other embodiments.

The terms used in this specification generally have their ordinarymeanings in the art, within the context of the disclosure, and in thespecific context where each term is used. Certain terms that are used todescribe the disclosure are discussed below, or elsewhere in thespecification, to provide additional guidance to the practitionerregarding the description of the disclosure. For convenience, certainterms may be highlighted, for example using italics and/or quotationmarks. The use of highlighting has no influence on the scope and meaningof a term; the scope and meaning of a term is the same, in the samecontext, whether or not it is highlighted. It will be appreciated thatsame thing can be said in more than one way.

Consequently, alternative language and synonyms may be used for any oneor more of the terms discussed herein, nor is any special significanceto be placed upon whether or not a term is elaborated or discussedherein. Synonyms for certain terms are provided. A recital of one ormore synonyms does not exclude the use of other synonyms. The use ofexamples anywhere in this specification, including examples of any termsdiscussed herein, is illustrative only, and is not intended to furtherlimit the scope and meaning of the disclosure or of any exemplifiedterm. Likewise, the disclosure is not limited to various embodimentsgiven in this specification.

Without intent to limit the scope of the disclosure, examples ofinstruments, apparatus, methods and their related results according tothe embodiments of the present disclosure are given below. Note thattitles or subtitles may be used in the examples for convenience of areader, which in no way should limit the scope of the disclosure. Unlessotherwise defined, all technical and scientific terms used herein havethe same meaning as commonly understood by one of ordinary skill in theart to which this disclosure pertains. In the case of conflict, thepresent document, including definitions, will control.

Embodiments of the present disclosure are directed to managingkeep-alive messaging and signaling in a distributed fashion formobile/broadband network resource conservation and optimization.

In one embodiment, a mobile client or mobile device (e.g., any wirelessdevice) is able to detect, determine, infer, or confirm the operationalor non-operational status of a server or other server-side component(and vice versa) using intelligently managed (e.g., based on real-time,near real-time, and/or historical communication rates andcharacteristics) keep-alive messages that are timed to decrease orminimize the signaling between the client and server needed to indicatehealthful status or otherwise.

Thus, disclosed herein is one effective mechanism of generating andexchanging a periodic keep-alive message or other types of heartbeats orindicators to convey a functional/operational state of a component, orotherwise causing a network connection to be maintained between thefunctional components that are adapted dynamically. The dynamicadaptation of periodic keep-alive message use, management and generationfor example, can be based on real-time or historical communicationstatistics so as to use the signaling in a manner that minimizes theimpact on network resource consumption. The real-time or historicalcommunication statistics can be determined, aggregated, and/or trackedusing components in a distributed system, such as a distributed proxysystem.

Embodiments of the present disclosure include systems and methods forcaching and adapting caching for mobile application behavior, useractivity/behavior, or network conditions.

There are multiple factors that contribute to the proliferation of data:the end-user, mobile devices, wireless devices, mobile applications, andthe network. As mobile devices evolve, so do the various elementsassociated with them-availability, applications, user behavior, locationthus changing the way the network interacts with the device and theapplication.

The disclosed technology provides a comprehensive and end-to-endsolution that is able to address each element for operators and devicesmanufacturers to support both the shift in mobile or wireless devicesand the surge in data by leveraging the premise that mobile content hasa definable or relevant “freshness” value. The “freshness” of mobilecontent can be determined, either with certainty, or with someheuristics having a tolerance within which the user experience isenhanced, or not negatively impacted, or negatively impacted but iseither not perceptible to the user or within a tolerable thresholdlevel.

The disclosed innovation transparently determines such “freshness” bymonitoring, analyzing, and applying rules (which may be heuristicallydetermined) the transactions (requests/responses) between applications(e.g., mobile applications) and the peers (corresponding server or otherclients). Moreover, the technology is further able to effectively cachecontent which may be marked by its originating/host server as being“non-cacheable” and identify some “freshness” value which can then beused in implementing application-specific caching. In general, the“freshness” value has an approximate minimum value which is typicallydetermined using the update interval (e.g., interval with which requestsare sent) between the application and its corresponding server/host.

One embodiment of the disclosed technology includes a system thatoptimizes multiple aspects of the connection with wired and wirelessnetworks and devices through a comprehensive view of device andapplication activity including: loading, current application needs on adevice, controlling the type of access (push vs. pull or hybrid),location, concentration of users in a single area, time of day, howoften the user interacts with the application, content or device, andusing this information to shape traffic to a cooperative client/serveror simultaneously mobile devices without a cooperative client. Becausethe disclosed server is not tied to any specific network provider it hasvisibility into the network performance across all service providers.This enables optimizations to be applied to devices regardless of theoperator or service provider, thereby enhancing the user experience andmanaging network utilization while roaming. Bandwidth has beenconsidered a major issue in wireless networks today. More and moreresearch has been done related to the need for additional bandwidth tosolve access problems. Many of the performance enhancing solutions andnext generation standards, such as those commonly referred to as 3.5G,LTE, 4G, and WiMAX, are focused on providing increased bandwidth.Although partially addressed by the standards, a key problem thatremains is lack of bandwidth on the signaling channel more so than thedata channel and the standard does not address battery life very well.

Embodiments of the disclosed technology includes, for example, alignmentof requests from multiple applications to minimize the need for severalpolling requests; leverage specific content types to determine how toproxy/manage a connection/content; and applying specific heuristicsassociated with device, user behavioral patterns (how often theyinteract with the device/application) and/or network parameters.

Embodiments of the present technology can further include, movingrecurring HTTP polls performed by various widgets, RSS readers, etc., toremote network node (e.g., Network Operation Center (NOC)), thusconsiderably lowering device battery/power consumption, radio channelsignaling and bandwidth usage. Additionally, the offloading can beperformed transparently so that existing applications do not need to bechanged.

In some embodiments, this can be implemented using a local proxy on themobile device (e.g., any wireless device) which automatically detectsrecurring requests for the same content (RSS feed, Widget data set) thatmatches a specific rule (e.g., happens every 15 minutes). The localproxy can automatically cache the content on the mobile device whiledelegating the polling to the server (e.g., a proxy server operated asan element of a communications network). The server can then notify themobile/client proxy if the content changes, and if content has notchanged (or not changed sufficiently, or in an identified manner oramount) the mobile proxy provides the latest version in its cache to theuser (without need to utilize the radio at all). This way the mobile orwireless device (e.g., a mobile phone, smart phone, M2M module/MODEM, orany other wireless devices, etc.) does not need to open (e.g., thuspowering on the radio) or use a data connection if the request is forcontent that is monitored and that has been not flagged as new/changed.

The logic for automatically adding content sources/application servers(e.g., including URLs/content) to be monitored can also check forvarious factors like how often the content is the same, how often thesame request is made (is there a fixed interval/pattern?), whichapplication is requesting the data, etc. Similar rules to decide betweenusing the cache and request the data from the original source may alsobe implemented and executed by the local proxy and/or server.

For example, when the request comes at an unscheduled/unexpected time(user initiated check), or after every (n) consecutive times theresponse has been provided from the cache, etc., or if the applicationis running in the background vs. in a more interactive mode of theforeground. As more and more mobile applications or wireless enabledapplications base their features on resources available in the network,this becomes increasingly important. In addition, the disclosedtechnology allows elimination of unnecessary chatter from the network,benefiting the operators trying to optimize the wireless spectrum usage.

Polling Schedule

Detecting (or determining) a polling schedule allows the proxy server(server-side of the distributed cache system) to be as close as possiblewith its polls to the application polls. Many applications employscheduled interval polling (e.g., every 4 hours or every 30 seconds, atanother time interval). The client side proxy can detect automatic pollsbased on time measurements and create a automatic polling profile for anapplication. As an example, the local proxy attempts to detect the timeinterval between requests and after 2, 3, 4, or more polls, determinesan automatic rate if the time intervals are all within 1 second (oranother measure of relative closeness) of each other. If not, the clientmay collect data from a greater number of polling events (e.g., 10-12polls) and apply a statistical analysis to determine, compute, orestimate a value for the average interval that is used. The pollingprofile is delivered to the server where it is used. If it is a frequentmanual request, the locally proxy can substitute it with a defaultinterval for this application taken from a profile for non-criticalapplications.

In some embodiments, the local proxy (e.g., device side proxy) may keepmonitoring the application/client polls and update the polling interval.If it changes by more than 30% (or anotherpredetermined/dynamic/conditional value) from the current value, it iscommunicated to the proxy server (e.g., server-side proxy). Thisapproach can be referred to as the scenario of “lost interest.” In someinstances, the local proxy can recognize requests made outside of thisschedule, consider them “manual,” and treat them accordingly.

Application Classes/Modes of Caching

In some embodiments, applications can be organized into three groups ormodes of caching. Each mobile client/application can be categorized tobe treated as one of these modes, or treated using multiple modes,depending on one or more conditions.

A) Fully cached—local proxy updates (e.g., sends application requestsdirectly over the network to be serviced by the applicationserver/content host) only when the proxy server tells the local proxy toupdate. In this mode, the local proxy can ignore manual requests and theproxy server uses the detected automatic profile (e.g., sports scoreapplets, Facebook, every 10, 15, 30, or more polls) to poll theapplication server/content provider.

B) Partially cached—the local proxy uses the local or internal cache forautomatic requests (e.g., application automatic refreshes), otherscheduled requests but passes through some manual requests (e.g., emaildownload, Ebay or some Facebook requests); and

C) Never cached (e.g., real-time stock ticker, sports scores/statuses;however, in some instances, 15 minutes delayed quotes can be safelyplaced on 30 seconds schedules—B or even A).

The actual application or caching mode classification can be determinedbased on the rate of content change and critical character of data.Unclassified applications by default can be set as class C.

Backlight and Active Applications

In some embodiments, the local proxy starts by detecting the devicebacklight status. Requests made with the screen light ‘off’ can beallowed to use the local cache if a request with identical signature isregistered with the proxy server, which is polling the original hostserver/content server(s) to which the requests are directed. If thescreen light is ‘on’, further detection can be made to determine whetherit is a background application or for other indicators that local cacheentries can or cannot be used to satisfy the request. When identified,the requests for which local entries can be used may be processedidentically to the screen light off situation. Foreground requests canuse the aforementioned application classification to assess when cacheddata is safe to use to process requests.

FIG. 1A illustrates an example diagram of a system where a host server100 facilitates management of traffic, content caching, and/or resourceconservation between clients (e.g., mobile devices, any wireless deviceor clients/applications on client devices 150) and an application serveror content provider 110 in a wireless network (or broad band network)106 or 108 for resource conservation.

The client devices 150 can be any system and/or device, and/or anycombination of devices/systems that is able to establish a connection,including wired, wireless, cellular connections with another device, aserver and/or other systems such as host server 100 and/or applicationserver/content provider 110. Client devices 150 will typically include adisplay and/or other output functionalities to present information anddata exchanged between among the devices 150 and/or the host server 100and/or application server/content provider 110.

For example, the client devices 150 can include mobile, hand held orportable devices, wireless devices, or non-portable devices and can beany of, but not limited to, a server desktop, a desktop computer, acomputer cluster, or portable devices, including a notebook, a laptopcomputer, a handheld computer, a palmtop computer, a mobile phone, acell phone, a smart phone, a PDA, a Blackberry device, a Palm device, ahandheld tablet (e.g., an iPad or any other tablet), a hand heldconsole, a hand held gaming device or console, any SuperPhone such asthe iPhone, and/or any other portable, mobile, hand held devices, orfixed wireless interface such as a M2M device, etc. In one embodiment,the client devices 150, host server 100, and application server 110 arecoupled via a network 106 and/or a network 108. In some embodiments, thedevices 150 and host server 100 may be directly connected to oneanother.

The input mechanism on client devices 150 can include touch screenkeypad (including single touch, multi-touch, gesture sensing in 2D or3D, etc.), a physical keypad, a mouse, a pointer, a track pad, motiondetector (e.g., including 1-axis, 2-axis, 3-axis accelerometer, etc.), alight sensor, capacitance sensor, resistance sensor, temperature sensor,proximity sensor, a piezoelectric device, device orientation detector(e.g., electronic compass, tilt sensor, rotation sensor, gyroscope,accelerometer), or a combination of the above.

Signals received or detected indicating user activity at client devices150 through one or more of the above input mechanism, or others, can beused in the disclosed technology in acquiring context awareness at theclient device 150. Context awareness at client devices 150 generallyincludes, by way of example but not limitation, client device 150operation or state acknowledgement, management, useractivity/behavior/interaction awareness, detection, sensing, tracking,trending, and/or application (e.g., mobile applications) type, behavior,activity, operating state, etc.

Context awareness in the present disclosure also includes knowledge anddetection of network side contextual data and can include networkinformation such as network capacity, bandwidth, traffic, type ofnetwork/connectivity, and/or any other operational state data. Networkside contextual data can be received from and/or queried from networkservice providers (e.g., cell provider 112 and/or Internet serviceproviders) of the network 106 and/or network 108 (e.g., by the hostserver and/or devices 150). In addition to application context awarenessas determined from the client 150 side, the application contextawareness may also be received from or obtained/queried from therespective application/service providers 110 (by the host 100 and/orclient devices 150).

The host server 100 can use, for example, contextual informationobtained for client devices 150, networks 106/108, applications (e.g.,mobile applications), application server/provider 110, or anycombination of the above, to manage the traffic in the system to satisfydata needs of the client devices 150 (e.g., to satisfy application orany other request including HTTP request). In one embodiment, thetraffic is managed by the host server 100 to satisfy data requests madein response to explicit or non-explicit user 103 requests and/ordevice/application maintenance tasks. The traffic can be managed suchthat network consumption, for example, use of the cellular network isconserved for effective and efficient bandwidth utilization. Inaddition, the host server 100 can manage and coordinate such traffic inthe system such that use of device 150 side resources (e.g., includingbut not limited to battery power consumption, radio use,processor/memory use) are optimized with a general philosophy forresource conservation while still optimizing performance and userexperience.

For example, in context of battery conservation, the device 150 canobserve user activity (for example, by observing user keystrokes,backlight status, or other signals via one or more input mechanisms,etc.) and alters device 150 behaviors. The device 150 can also requestthe host server 100 to alter the behavior for network resourceconsumption based on user activity or behavior.

In one embodiment, the traffic management for resource conservation isperformed using a distributed system between the host server 100 andclient device 150. The distributed system can include proxy server andcache components on the server side 100 and on the device/client side,for example, as shown by the server cache 135 on the server 100 side andthe local cache 185 on the client 150 side.

Functions and techniques disclosed for context aware traffic managementfor resource conservation in networks (e.g., network 106 and/or 108) anddevices 150, reside in a distributed proxy and cache system. The proxyand cache system can be distributed between, and reside on, a givenclient device 150 in part or in whole and/or host server 100 in part orin whole. The distributed proxy and cache system are illustrated withfurther reference to the example diagram shown in FIG. 1B. Functions andtechniques performed by the proxy and cache components in the clientdevice 150, the host server 100, and the related components therein aredescribed, respectively, in detail with further reference to theexamples of FIG. 2-3.

In one embodiment, client devices 150 communicate with the host server100 and/or the application server 110 over network 106, which can be acellular network and/or a broadband network. To facilitate overalltraffic management between devices 150 and various applicationservers/content providers 110 to implement network (bandwidthutilization) and device resource (e.g., battery consumption), the hostserver 100 can communicate with the application server/providers 110over the network 108, which can include the Internet (e.g., a broadbandnetwork).

In general, the networks 106 and/or 108, over which the client devices150, the host server 100, and/or application server 110 communicate, maybe a cellular network, a broadband network, a telephonic network, anopen network, such as the Internet, or a private network, such as anintranet and/or the extranet, or any combination thereof. For example,the Internet can provide file transfer, remote log in, email, news, RSS,cloud-based services, instant messaging, visual voicemail, push mail,VoIP, and other services through any known or convenient protocol, suchas, but is not limited to the TCP/IP protocol, UDP, HTTP, DNS, FTP,UPnP, NSF, ISDN, PDH, RS-232, SDH, SONET, etc.

The networks 106 and/or 108 can be any collection of distinct networksoperating wholly or partially in conjunction to provide connectivity tothe client devices 150 and the host server 100 and may appear as one ormore networks to the serviced systems and devices. In one embodiment,communications to and from the client devices 150 can be achieved by, anopen network, such as the Internet, or a private network, broadbandnetwork, such as an intranet and/or the extranet. In one embodiment,communications can be achieved by a secure communications protocol, suchas secure sockets layer (SSL), or transport layer security (TLS).

In addition, communications can be achieved via one or more networks,such as, but are not limited to, one or more of WiMax, a Local AreaNetwork (LAN), Wireless Local Area Network (WLAN), a Personal areanetwork (PAN), a Campus area network (CAN), a Metropolitan area network(MAN), a Wide area network (WAN), a Wireless wide area network (WWAN),or any broadband network, and further enabled with technologies such as,by way of example, Global System for Mobile Communications (GSM),Personal Communications Service (PCS), Bluetooth, WiFi, Fixed WirelessData, 2G, 2.5G, 3G, 4G, IMT-Advanced, pre-4G, LTE Advanced, mobileWiMax, WiMax 2, WirelessMAN-Advanced networks, enhanced data rates forGSM evolution (EDGE), General packet radio service (GPRS), enhancedGPRS, iBurst, UMTS, HSPDA, HSUPA, HSPA, UMTS-TDD, 1×RTT, EV-DO,messaging protocols such as, TCP/IP, SMS, MMS, extensible messaging andpresence protocol (XMPP), real time messaging protocol (RTMP), instantmessaging and presence protocol (IMPP), instant messaging, USSD, IRC, orany other wireless data networks, broadband networks, or messagingprotocols.

FIG. 1B illustrates an example diagram of a proxy and cache systemdistributed between the host server 100 and device 150 which facilitatesnetwork traffic management between the device 150 and an applicationserver/content provider 100 (e.g., a source server) for resourceconservation and content caching.

The distributed proxy and cache system can include, for example, theproxy server 125 (e.g., remote proxy) and the server cache, 135components on the server side. The server-side proxy 125 and cache 135can, as illustrated, reside internal to the host server 100. Inaddition, the proxy server 125 and cache 135 on the server-side can bepartially or wholly external to the host server 100 and in communicationvia one or more of the networks 106 and 108. For example, the proxyserver 125 may be external to the host server and the server cache 135may be maintained at the host server 100. Alternatively, the proxyserver 125 may be within the host server 100 while the server cache isexternal to the host server 100. In addition, each of the proxy server125 and the cache 135 may be partially internal to the host server 100and partially external to the host server 100.

The distributed system can also, include, in one embodiment, client-sidecomponents, including by way of example but not limitation, a localproxy 175 (e.g., a mobile client on a mobile device) and/or a localcache 185, which can, as illustrated, reside internal to the device 150(e.g., a mobile device).

In addition, the client-side proxy 175 and local cache 185 can bepartially or wholly external to the device 150 and in communication viaone or more of the networks 106 and 108. For example, the local proxy175 may be external to the device 150 and the local cache 185 may bemaintained at the device 150. Alternatively, the local proxy 175 may bewithin the device 150 while the local cache 185 is external to thedevice 150. In addition, each of the proxy 175 and the cache 185 may bepartially internal to the host server 100 and partially external to thehost server 100.

In one embodiment, the distributed system can include an optionalcaching proxy server 199. The caching proxy server 199 can be acomponent which is operated by the application server/content provider110, the host server 100, or a network service provider 112, and or anycombination of the above to facilitate network traffic management fornetwork and device resource conservation. Proxy server 199 can be used,for example, for caching content to be provided to the device 150, forexample, from one or more of, the application server/provider 110, hostserver 100, and/or a network service provider 112. Content caching canalso be entirely or partially performed by the remote proxy 125 tosatisfy application requests or other data requests at the device 150.

In context aware traffic management and optimization for resourceconservation in a network (e.g., cellular or other wireless networks),characteristics of user activity/behavior and/or application behavior ata mobile device (e.g., any wireless device) 150 can be tracked by thelocal proxy 175 and communicated, over the network 106 to the proxyserver 125 component in the host server 100, for example, as connectionmetadata. The proxy server 125 which in turn is coupled to theapplication server/provider 110 provides content and data to satisfyrequests made at the device 150.

In addition, the local proxy 175 can identify and retrieve mobile deviceproperties, including one or more of, battery level, network that thedevice is registered on, radio state, or whether the mobile device isbeing used (e.g., interacted with by a user). In some instances, thelocal proxy 175 can delay, expedite (prefetch), and/or modify data priorto transmission to the proxy server 125, when appropriate, as will befurther detailed with references to the description associated with theexamples of FIG. 2-3.

The local database 185 can be included in the local proxy 175 or coupledto the local proxy 175 and can be queried for a locally stored responseto the data request prior to the data request being forwarded on to theproxy server 125. Locally cached responses can be used by the localproxy 175 to satisfy certain application requests of the mobile device150, by retrieving cached content stored in the cache storage 185, whenthe cached content is still valid.

Similarly, the proxy server 125 of the host server 100 can also delay,expedite, or modify data from the local proxy prior to transmission tothe content sources (e.g., the application server/content provider 110).In addition, the proxy server 125 uses device properties and connectionmetadata to generate rules for satisfying request of applications on themobile device 150. The proxy server 125 can gather real time trafficinformation about requests of applications for later use in optimizingsimilar connections with the mobile device 150 or other mobile devices.

In general, the local proxy 175 and the proxy server 125 are transparentto the multiple applications executing on the mobile device. The localproxy 175 is generally transparent to the operating system or platformof the mobile device and may or may not be specific to devicemanufacturers. In some instances, the local proxy 175 is optionallycustomizable in part or in whole to be device specific. In someembodiments, the local proxy 175 may be bundled into a wireless model, afirewall, and/or a router.

In one embodiment, the host server 100 can in some instances, utilizethe store and forward functions of a short message service center (SMSC)112, such as that provided by the network service provider, incommunicating with the device 150 in achieving network trafficmanagement. Note that 112 can also utilize any other type of alternativechannel including USSD or other network control mechanisms. As will befurther described with reference to the example of FIG. 3, the hostserver 100 can forward content or HTTP responses to the SMSC 112 suchthat it is automatically forwarded to the device 150 if available, andfor subsequent forwarding if the device 150 is not currently available.

In general, the disclosed distributed proxy and cache system allowsoptimization of network usage, for example, by serving requests from thelocal cache 185, the local proxy 175 reduces the number of requests thatneed to be satisfied over the network 106. Further, the local proxy 175and the proxy server 125 may filter irrelevant data from thecommunicated data. In addition, the local proxy 175 and the proxy server125 can also accumulate low priority data and send it in batches toavoid the protocol overhead of sending individual data fragments. Thelocal proxy 175 and the proxy server 125 can also compress or transcodethe traffic, reducing the amount of data sent over the network 106and/or 108. The signaling traffic in the network 106 and/or 108 can bereduced, as the networks are now used less often and the network trafficcan be synchronized among individual applications.

With respect to the battery life of the mobile device 150, by servingapplication or content requests from the local cache 185, the localproxy 175 can reduce the number of times the radio module is powered up.The local proxy 175 and the proxy server 125 can work in conjunction toaccumulate low priority data and send it in batches to reduce the numberof times and/or amount of time when the radio is powered up. The localproxy 175 can synchronize the network use by performing the batched datatransfer for all connections simultaneously.

FIG. 2A depicts a block diagram illustrating an example of client-sidecomponents in a distributed proxy and cache system residing on a device250 that manages traffic in a wireless network for resourceconservation, content caching, and/or traffic management.

The device 250, which can be a portable or mobile device (e.g., anywireless device), such as a portable phone, generally includes, forexample, a network interface 208208 an operating system 204, a contextAPI 206, and mobile applications which may be proxy-unaware 210 orproxy-aware 220. Note that the device 250 is specifically illustrated inthe example of FIG. 2 as a mobile device, such is not a limitation andthat device 250 may be any portable/mobile or non-portable device ableto receive, transmit signals to satisfy data requests over a networkincluding wired or wireless networks (e.g., WiFi, cellular, Bluetooth,etc.).

The network interface 208 can be a networking module that enables thedevice 250 to mediate data in a network with an entity that is externalto the host server 250, through any known and/or convenientcommunications protocol supported by the host and the external entity.The network interface 208 can include one or more of a network adaptorcard, a wireless network interface card (e.g., SMS interface, WiFiinterface, interfaces for various generations of mobile communicationstandards including but not limited to 2G, 3G, 3.5G, 4G, LTE, etc.),Bluetooth, or whether or not the connection is via a router, an accesspoint, a wireless router, a switch, a multilayer switch, a protocolconverter, a gateway, a bridge, a bridge router, a hub, a digital mediareceiver, and/or a repeater.

Device 250 can further include, client-side components of thedistributed proxy and cache system which can include, a local proxy 275(e.g., a mobile client of a mobile device) and a cache 285. In oneembodiment, the local proxy 275 includes a user activity module 215, aproxy API 225, a request/transaction manager 235, a caching policymanager 245 having an application protocol module 248, a traffic shapingengine 255, and/or a connection manager 265. The traffic shaping engine255 may further include an alignment module 256 and/or a batching module257, the connection manager 265 may further include a radio controller266. The request/transaction manager 235 can further include anapplication behavior detector 236 and/or a prioritization engine 241,the application behavior detector 236 may further include a patterndetector 237 and/or and application profile generator 239. Additional orless components/modules/engines can be included in the local proxy 275and each illustrated component.

As used herein, a “module,” “a manager,” a “handler,” a “detector,” an“interface,” a “controller,” a “normalizer,” a “generator,” an“invalidator,” or an “engine” includes a general purpose, dedicated orshared processor and, typically, firmware or software modules that areexecuted by the processor. Depending upon implementation-specific orother considerations, the module, manager, handler, detector, interface,controller, normalizer, generator, invalidator, or engine can becentralized or its functionality distributed. The module, manager,handler, detector, interface, controller, normalizer, generator,invalidator, or engine can include general or special purpose hardware,firmware, or software embodied in a computer-readable (storage) mediumfor execution by the processor.

As used herein, a computer-readable medium or computer-readable storagemedium is intended to include all mediums that are statutory (e.g., inthe United States, under 35 U.S.C. 101), and to specifically exclude allmediums that are non-statutory in nature to the extent that theexclusion is necessary for a claim that includes the computer-readable(storage) medium to be valid. Known statutory computer-readable mediumsinclude hardware (e.g., registers, random access memory (RAM),non-volatile (NV) storage, to name a few), but may or may not be limitedto hardware.

In one embodiment, a portion of the distributed proxy and cache systemfor network traffic management resides in or is in communication withdevice 250, including local proxy 275 (mobile client) and/or cache 285.The local proxy 275 can provide an interface on the device 250 for usersto access device applications and services including email, IM, voicemail, visual voicemail, feeds, Internet, games, productivity tools, orother applications, etc.

The proxy 275 is generally application independent and can be used byapplications (e.g., both proxy-aware and proxy-unaware applications 210and 220 or mobile applications) to open TCP connections to a remoteserver (e.g., the server 100 in the examples of FIG. 1A-1B and/or serverproxy 125/325 shown in the examples of FIG. 1B and FIG. 3A). In someinstances, the local proxy 275 includes a proxy API 225 which can beoptionally used to interface with proxy-aware applications 220 (orapplications (e.g., mobile applications) on a mobile device (e.g., anywireless device)).

The applications 210 and 220 can generally include any user application,widgets, software, HTTP-based application, web browsers, video or othermultimedia streaming or downloading application, video games, socialnetwork applications, email clients, RSS management applications,application stores, document management applications, productivityenhancement applications, etc. The applications can be provided with thedevice OS, by the device manufacturer, by the network service provider,downloaded by the user, or provided by others.

One embodiment of the local proxy 275 includes or is coupled to acontext API 206, as shown. The context API 206 may be a part of theoperating system 204 or device platform or independent of the operatingsystem 204, as illustrated. The operating system 204 can include anyoperating system including but not limited to, any previous, current,and/or future versions/releases of, Windows Mobile, iOS, Android,Symbian, Palm OS, Brew MP, Java 2 Micro Edition (J2ME), Blackberry, etc.

The context API 206 may be a plug-in to the operating system 204 or aparticular client/application on the device 250. The context API 206 candetect signals indicative of user or device activity, for example,sensing motion, gesture, device location, changes in device location,device backlight, keystrokes, clicks, activated touch screen, mouseclick or detection of other pointer devices. The context API 206 can becoupled to input devices or sensors on the device 250 to identify thesesignals. Such signals can generally include input received in responseto explicit user input at an input device/mechanism at the device 250and/or collected from ambient signals/contextual cues detected at or inthe vicinity of the device 250 (e.g., light, motion, piezoelectric,etc.).

In one embodiment, the user activity module 215 interacts with thecontext API 206 to identify, determine, infer, detect, compute, predict,and/or anticipate, characteristics of user activity on the device 250.Various inputs collected by the context API 206 can be aggregated by theuser activity module 215 to generate a profile for characteristics ofuser activity. Such a profile can be generated by the user activitymodule 215 with various temporal characteristics. For instance, useractivity profile can be generated in real-time for a given instant toprovide a view of what the user is doing or not doing at a given time(e.g., defined by a time window, in the last minute, in the last 30seconds, etc.), a user activity profile can also be generated for a‘session’ defined by an application or web page that describes thecharacteristics of user behavior with respect to a specific task theyare engaged in on the device 250, or for a specific time period (e.g.,for the last 2 hours, for the last 5 hours).

Additionally, characteristic profiles can be generated by the useractivity module 215 to depict a historical trend for user activity andbehavior (e.g., 1 week, 1 mo., 2 mo., etc.). Such historical profilescan also be used to deduce trends of user behavior, for example, accessfrequency at different times of day, trends for certain days of the week(weekends or week days), user activity trends based on location data(e.g., IP address, GPS, or cell tower coordinate data) or changes inlocation data (e.g., user activity based on user location, or useractivity based on whether the user is on the go, or traveling outside ahome region, etc.) to obtain user activity characteristics.

In one embodiment, user activity module 215 can detect and track useractivity with respect to applications, documents, files, windows, icons,and folders on the device 250. For example, the user activity module 215can detect when an application or window (e.g., a web browser or anyother type of application) has been exited, closed, minimized,maximized, opened, moved into the foreground, or into the background,multimedia content playback, etc.

In one embodiment, characteristics of the user activity on the device250 can be used to locally adjust behavior of the device (e.g., mobiledevice or any wireless device) to optimize its resource consumption suchas battery/power consumption and more generally, consumption of otherdevice resources including memory, storage, and processing power. In oneembodiment, the use of a radio on a device can be adjusted based oncharacteristics of user behavior (e.g., by the radio controller 266 ofthe connection manager 265) coupled to the user activity module 215. Forexample, the radio controller 266 can turn the radio on or off, based oncharacteristics of the user activity on the device 250. In addition, theradio controller 266 can adjust the power mode of the radio (e.g., to bein a higher power mode or lower power mode) depending on characteristicsof user activity.

In one embodiment, characteristics of the user activity on device 250can also be used to cause another device (e.g., other computers, amobile device, a wireless device, or a non-portable device) or server(e.g., host server 100 and 300 in the examples of FIG. 1A-B and FIG. 3A)which can communicate (e.g., via a cellular or other network) with thedevice 250 to modify its communication frequency with the device 250.The local proxy 275 can use the characteristics information of userbehavior determined by the user activity module 215 to instruct theremote device as to how to modulate its communication frequency (e.g.,decreasing communication frequency, such as data push frequency if theuser is idle, requesting that the remote device notify the device 250 ifnew data, changed, data, or data of a certain level of importancebecomes available, etc.).

In one embodiment, the user activity module 215 can, in response todetermining that user activity characteristics indicate that a user isactive after a period of inactivity, request that a remote device (e.g.,server host server 100 and 300 in the examples of FIG. 1A-B and FIG. 3A)send the data that was buffered as a result of the previously decreasedcommunication frequency.

In addition, or in alternative, the local proxy 275 can communicate thecharacteristics of user activity at the device 250 to the remote device(e.g., host server 100 and 300 in the examples of FIG. 1A-B and FIG. 3A)and the remote device determines how to alter its own communicationfrequency with the device 250 for network resource conservation andconservation of device 250 resources.

One embodiment of the local proxy 275 further includes arequest/transaction manager 235, which can detect, identify, intercept,process, manage, data requests initiated on the device 250, for example,by applications 210 and/or 220, and/or directly/indirectly by a userrequest. The request/transaction manager 235 can determine how and whento process a given request or transaction, or a set ofrequests/transactions, based on transaction characteristics.

The request/transaction manager 235 can prioritize requests ortransactions made by applications and/or users at the device 250, forexample by the prioritization engine 241. Importance or priority ofrequests/transactions can be determined by the request/transactionmanager 235 by applying a rule set, for example, according to timesensitivity of the transaction, time sensitivity of the content in thetransaction, time criticality of the transaction, time criticality ofthe data transmitted in the transaction, and/or time criticality orimportance of an application making the request.

In addition, transaction characteristics can also depend on whether thetransaction was a result of user-interaction or other user-initiatedaction on the device (e.g., user interaction with a application (e.g., amobile application)). In general, a time critical transaction caninclude a transaction resulting from a user-initiated data transfer, andcan be prioritized as such. Transaction characteristics can also dependon the amount of data that will be transferred or is anticipated to betransferred as a result of the requested transaction. For example, theconnection manager 265, can adjust the radio mode (e.g., high power orlow power mode via the radio controller 266) based on the amount of datathat will need to be transferred.

In addition, the radio controller 266/connection manager 265 can adjustthe radio power mode (high or low) based on time criticality/sensitivityof the transaction. The radio controller 266 can trigger the use of highpower radio mode when a time-critical transaction (e.g., a transactionresulting from a user-initiated data transfer, an application running inthe foreground, any other event meeting a certain criteria) is initiatedor detected.

In general, the priorities can be set by default, for example, based ondevice platform, device manufacturer, operating system, etc. Prioritiescan alternatively or in additionally be set by the particularapplication; for example, the Facebook application (e.g., a mobileapplication) can set its own priorities for various transactions (e.g.,a status update can be of higher priority than an add friend request ora poke request, a message send request can be of higher priority than amessage delete request, for example), an email client or IM chat clientmay have its own configurations for priority. The prioritization engine241 may include set of rules for assigning priority.

The prioritization engine 241 can also track network providerlimitations or specifications on application or transaction priority indetermining an overall priority status for a request/transaction.Furthermore, priority can in part or in whole be determined by userpreferences, either explicit or implicit. A user, can in general, setpriorities at different tiers, such as, specific priorities forsessions, or types, or applications (e.g., a browsing session, a gamingsession, versus an IM chat session, the user may set a gaming session toalways have higher priority than an IM chat session, which may havehigher priority than web-browsing session). A user can setapplication-specific priorities, (e.g., a user may set Facebook-relatedtransactions to have a higher priority than LinkedIn-relatedtransactions), for specific transaction types (e.g., for all sendmessage requests across all applications to have higher priority thanmessage delete requests, for all calendar-related events to have a highpriority, etc.), and/or for specific folders.

The prioritization engine 241 can track and resolve conflicts inpriorities set by different entities. For example, manual settingsspecified by the user may take precedence over device OS settings,network provider parameters/limitations (e.g., set in default for anetwork service area, geographic locale, set for a specific time of day,or set based on service/fee type) may limit any user-specified settingsand/or application-set priorities. In some instances, a manualsynchronization request received from a user can override some, most, orall priority settings in that the requested synchronization is performedwhen requested, regardless of the individually assigned priority or anoverall priority ranking for the requested action.

Priority can be specified and tracked internally in any known and/orconvenient manner, including but not limited to, a binaryrepresentation, a multi-valued representation, a graded representationand all are considered to be within the scope of the disclosedtechnology.

TABLE I Change Change (initiated on device) Priority (initiated onserver) Priority Send email High Receive email High Delete email LowEdit email Often not possible to sync (Low if possible) (Un)read emailLow Move message Low New email in deleted items Low Read more HighDownload High Delete an email Low attachment (Un)Read an email Low NewCalendar event High Move messages Low Edit/change Calendar event HighAny calendar change High Any contact change High Add a contact HighWipe/lock device High Edit a contact High Settings change High Searchcontacts High Any folder change High Change a setting High Connectorrestart High (if no changes nothing is sent) Manual send/receive High IMstatus change Medium Social Network Status Updates Medium Auction outbidor change High Sever Weather Alerts High notification Weather UpdatesLow News Updates Low

Table I above shows, for illustration purposes, some examples oftransactions with examples of assigned priorities in a binaryrepresentation scheme. Additional assignments are possible foradditional types of events, requests, transactions, and as previouslydescribed, priority assignments can be made at more or less granularlevels, e.g., at the session level or at the application level, etc.

As shown by way of example in the above table, in general, lowerpriority requests/transactions can include, updating message status asbeing read, unread, deleting of messages, deletion of contacts; higherpriority requests/transactions, can in some instances include, statusupdates, new IM chat message, new email, calendar eventupdate/cancellation/deletion, an event in a mobile gaming session, orother entertainment related events, a purchase confirmation through aweb purchase or online, request to load additional or download content,contact book related events, a transaction to change a device setting,location-aware or location-based events/transactions, or any otherevents/request/transactions initiated by a user or where the user isknown to be, expected to be, or suspected to be waiting for a response,etc.

Inbox pruning events (e.g., email, or any other types of messages), aregenerally considered low priority and absent other impending events,generally will not trigger use of the radio on the device 250.Specifically, pruning events to remove old email or other content can be‘piggy backed’ with other communications if the radio is not otherwiseon, at the time of a scheduled pruning event. For example, if the userhas preferences set to ‘keep messages for 7 days old,’ then instead ofpowering on the device radio to initiate a message delete from thedevice 250 the moment that the message has exceeded 7 days old, themessage is deleted when the radio is powered on next. If the radio isalready on, then pruning may occur as regularly scheduled.

The request/transaction manager 235, can use the priorities for requests(e.g., by the prioritization engine 241) to manage outgoing traffic fromthe device 250 for resource optimization (e.g., to utilize the deviceradio more efficiently for battery conservation). For example,transactions/requests below a certain priority ranking may not triggeruse of the radio on the device 250 if the radio is not already switchedon, as controlled by the connection manager 265. In contrast, the radiocontroller 266 can turn on the radio such a request can be sent when arequest for a transaction is detected to be over a certain prioritylevel.

In one embodiment, priority assignments (such as that determined by thelocal proxy 275 or another device/entity) can be used cause a remotedevice to modify its communication with the frequency with the mobiledevice or wireless device. For example, the remote device can beconfigured to send notifications to the device 250 when data of higherimportance is available to be sent to the mobile device or wirelessdevice.

In one embodiment, transaction priority can be used in conjunction withcharacteristics of user activity in shaping or managing traffic, forexample, by the traffic shaping engine 255. For example, the trafficshaping engine 255 can, in response to detecting that a user is dormantor inactive, wait to send low priority transactions from the device 250,for a period of time. In addition, the traffic shaping engine 255 canallow multiple low priority transactions to accumulate for batchtransferring from the device 250 (e.g., via the batching module 257), Inone embodiment, the priorities can be set, configured, or readjusted bya user. For example, content depicted in Table I in the same or similarform can be accessible in a user interface on the device 250 and forexample, used by the user to adjust or view the priorities.

The batching module 257 can initiate batch transfer based on certaincriteria. For example, batch transfer (e.g., of multiple occurrences ofevents, some of which occurred at different instances in time) may occurafter a certain number of low priority events have been detected, orafter an amount of time elapsed after the first of the low priorityevent was initiated. In addition, the batching module 257 can initiatebatch transfer of the cumulated low priority events when a higherpriority event is initiated or detected at the device 250. Batchtransfer can otherwise be initiated when radio use is triggered foranother reason (e.g., to receive data from a remote device such as hostserver 100 or 300). In one embodiment, an impending pruning event(pruning of an inbox), or any other low priority events, can be executedwhen a batch transfer occurs.

In general, the batching capability can be disabled or enabled at theevent/transaction level, application level, or session level, based onany one or combination of the following: user configuration, devicelimitations/settings, manufacturer specification, network providerparameters/limitations, platform-specific limitations/settings, deviceOS settings, etc. In one embodiment, batch transfer can be initiatedwhen an application/window/file is closed out, exited, or moved into thebackground; users can optionally be prompted before initiating a batchtransfer; users can also manually trigger batch transfers.

In one embodiment, the local proxy 275 locally adjusts radio use on thedevice 250 by caching data in the cache 285. When requests ortransactions from the device 250 can be satisfied by content stored inthe cache 285, the radio controller 266 need not activate the radio tosend the request to a remote entity (e.g., the host server 100, 300, asshown in FIG. 1A and FIG. 3A or a content provider/application serversuch as the server/provider 110 shown in the examples of FIG. 1A andFIG. 1B). As such, the local proxy 275 can use the local cache 285 andthe cache policy manager 245 to locally store data for satisfying datarequests to eliminate or reduce the use of the device radio forconservation of network resources and device battery consumption.

In leveraging the local cache, once the request/transaction manager 225intercepts a data request by an application on the device 250, the localrepository 285 can be queried to determine if there is any locallystored response, and also determine whether the response is valid. Whena valid response is available in the local cache 285, the response canbe provided to the application on the device 250 without the device 250needing to access the cellular network or wireless broadband network.

If a valid response is not available, the local proxy 275 can query aremote proxy (e.g., the server proxy 325 of FIG. 3A) to determinewhether a remotely stored response is valid. If so, the remotely storedresponse (e.g., which may be stored on the server cache 135 or optionalcaching server 199 shown in the example of FIG. 1B) can be provided tothe mobile device, possibly without the mobile device 250 needing toaccess the cellular network, thus relieving consumption of networkresources.

If a valid cache response is not available, or if cache responses areunavailable for the intercepted data request, the local proxy 275, forexample, the caching policy manager 245, can send the data request to aremote proxy (e.g., server proxy 325 of FIG. 3A) which forwards the datarequest to a content source (e.g., application server/content provider110 of FIG. 1A) and a response from the content source can be providedthrough the remote proxy, as will be further described in thedescription associated with the example host server 300 of FIG. 3A. Thecache policy manager 245 can manage or process requests that use avariety of protocols, including but not limited to HTTP, HTTPS, IMAP,POP, SMTP, XMPP, and/or ActiveSync. The caching policy manager 245 canlocally store responses for data requests in the local database 285 ascache entries, for subsequent use in satisfying same or similar datarequests.

The caching policy manager 245 can request that the remote proxy monitorresponses for the data request and the remote proxy can notify thedevice 250 when an unexpected response to the data request is detected.In such an event, the cache policy manager 245 can erase or replace thelocally stored response(s) on the device 250 when notified of theunexpected response (e.g., new data, changed data, additional data,etc.) to the data request. In one embodiment, the caching policy manager245 is able to detect or identify the protocol used for a specificrequest, including but not limited to HTTP, HTTPS, IMAP, POP, SMTP,XMPP, and/or ActiveSync. In one embodiment, application specifichandlers (e.g., via the application protocol module 246 of the cachingpolicy manager 245) on the local proxy 275 allows for optimization ofany protocol that can be port mapped to a handler in the distributedproxy (e.g., port mapped on the proxy server 325 in the example of FIG.3A).

In one embodiment, the local proxy 275 notifies the remote proxy suchthat the remote proxy can monitor responses received for the datarequest from the content source for changed results prior to returningthe result to the device 250, for example, when the data request to thecontent source has yielded same results to be returned to the mobiledevice. In general, the local proxy 275 can simulate application serverresponses for applications on the device 250, using locally cachedcontent. This can prevent utilization of the cellular network fortransactions where new/changed data is not available, thus freeing upnetwork resources and preventing network congestion.

In one embodiment, the local proxy 275 includes an application behaviordetector 236 to track, detect, observe, monitor, applications (e.g.,proxy-aware and/or unaware applications 210 and 220) accessed orinstalled on the device 250. Application behaviors, or patterns indetected behaviors (e.g., via the pattern detector 237) of one or moreapplications accessed on the device 250 can be used by the local proxy275 to optimize traffic in a wireless network needed to satisfy the dataneeds of these applications.

For example, based on detected behavior of multiple applications, thetraffic shaping engine 255 can align content requests made by at leastsome of the applications over the network (wireless network) (e.g., viathe alignment module 256). The alignment module 256 can delay orexpedite some earlier received requests to achieve alignment. Whenrequests are aligned, the traffic shaping engine 255 can utilize theconnection manager to poll over the network to satisfy application datarequests. Content requests for multiple applications can be alignedbased on behavior patterns or rules/settings including, for example,content types requested by the multiple applications (audio, video,text, etc.), device (e.g., mobile or wireless device) parameters, and/ornetwork parameters/traffic conditions, network service providerconstraints/specifications, etc.

In one embodiment, the pattern detector 237 can detect recurrences inapplication requests made by the multiple applications, for example, bytracking patterns in application behavior. A tracked pattern caninclude, detecting that certain applications, as a background process,poll an application server regularly, at certain times of day, oncertain days of the week, periodically in a predictable fashion, with acertain frequency, with a certain frequency in response to a certaintype of event, in response to a certain type user query, frequency thatrequested content is the same, frequency with which a same request ismade, interval between requests, applications making a request, or anycombination of the above, for example.

Such recurrences can be used by traffic shaping engine 255 to offloadpolling of content from a content source (e.g., from an applicationserver/content provider 110 of FIG. 1A) that would result from theapplication requests that would be performed at the mobile device orwireless device 250 to be performed instead, by a proxy server (e.g.,proxy server 125 of FIG. 1B or proxy server 325 of FIG. 3A) remote fromthe device 250. Traffic shaping engine 255 can decide to offload thepolling when the recurrences match a rule. For example, there aremultiple occurrences or requests for the same resource that have exactlythe same content, or returned value, or based on detection of repeatabletime periods between requests and responses such as a resource that isrequested at specific times during the day. The offloading of thepolling can decrease the amount of bandwidth consumption needed by themobile device 250 to establish a wireless (cellular or other wirelessbroadband) connection with the content source for repetitive contentpolls.

As a result of the offloading of the polling, locally cached contentstored in the local cache 285 can be provided to satisfy data requestsat the device 250, when content change is not detected in the polling ofthe content sources. As such, when data has not changed, applicationdata needs can be satisfied without needing to enable radio use oroccupying cellular bandwidth in a wireless network. When data haschanged and/or new data has been received, the remote entity to whichpolling is offloaded, can notify the device 250. The remote entity maybe the host server 300 as shown in the example of FIG. 3A.

In one embodiment, the local proxy 275 can mitigate or otherwise managethe need/use of periodic keep-alive messages (heartbeat messages) tomaintain TCP/IP connections, which can consume significant amounts ofpower thus having detrimental impacts on mobile device battery life. Theconnection manager 265 in the local proxy 275 (e.g., the heartbeatmanager 267) can detect, identify, and intercept any or all heartbeat(keep-alive) messages being sent from applications.

The heartbeat manager 267 can prevent any or all of these heartbeatmessages from being sent over the cellular, or other network, andinstead or in addition rely on the server component (e.g., proxy server125 or 325) of the distributed proxy system (e.g., shown in FIG. 1B) togenerate the and send the heartbeat messages to maintain a connectionwith the backend (e.g., application server/provider 110 in the exampleof FIG. 1A). The heartbeat manager 267 can also receive periodicmessages or keep-alive messages sent from the proxy server 125 or 325.Such keep-alive messages can be used to signal health or operationalstatus of the proxy server 125 or 325. The functions and features of theheartbeat manager 267 are further illustrated in the example of FIG. 2C.

The local proxy 275 generally represents any one or a portion of thefunctions described for the individual managers, modules, and/orengines. The local proxy 275 and device 250 can include additional orless components; more or less functions can be included, in whole or inpart, without deviating from the novel art of the disclosure.

FIG. 2B depicts a block diagram illustrating a further example ofcomponents in the cache system shown in the example of FIG. 2A which iscapable of caching and adapting caching strategies for mobileapplication behavior and/or network conditions.

In one embodiment, the caching policy manager 245 includes a metadatagenerator 203, a cache look-up engine 205, a cache appropriatenessdecision engine 246, a poll schedule generator 247, an applicationprotocol module 248, a cache or connect selection engine 249 and/or alocal cache invalidator 244. The cache appropriateness decision engine246 can further include a timing predictor 246 a, a content predictor246 b, a request analyzer 246 c, and/or a response analyzer 246 d, andthe cache or connect selection engine 249 includes a response scheduler249 a. The metadata generator 203 and/or the cache look-up engine 205are coupled to the cache 285 (or local cache) for modification oraddition to cache entries or querying thereof.

The cache look-up engine 205 may further include an ID or URI filter 205a, the local cache invalidator 244 may further include a TTL manager 244a, and the poll schedule generator 247 may further include a scheduleupdate engine 247 a and/or a time adjustment engine 247 b. Oneembodiment of caching policy manager 245 includes an application cachepolicy repository 243. In one embodiment, the application behaviordetector 236 includes a pattern detector 237, a poll interval detector238, an application profile generator 239, and/or a priority engine 241.The poll interval detector 238 may further include a long poll detector238 a having a response/request tracking engine 238 b. The poll intervaldetector 238 may further include a long poll hunting detector 238 c. Theapplication profile generator 239 can further include a response delayinterval tracker 239 a.

The pattern detector 237, application profile generator 239, and thepriority engine 241 were also described in association with thedescription of the pattern detector shown in the example of FIG. 2A. Oneembodiment further includes an application profile repository 242 whichcan be used by the local proxy 275 to store information or metadataregarding application profiles (e.g., behavior, patterns, type of HTTPrequests, etc.)

The cache appropriateness decision engine 246 can detect, assess, ordetermine whether content from a content source (e.g., applicationserver/content provider 110 in the example of FIG. 1B) with which amobile device 250 interacts and has content that may be suitable forcaching. For example, the decision engine 246 can use information abouta request and/or a response received for the request initiated at themobile device 250 to determine cacheability, potential cacheability, ornon-cacheability. In some instances, the decision engine 246 caninitially verify whether a request is directed to a blacklisteddestination or whether the request itself originates from a blacklistedclient or application. If so, additional processing and analysis may notbe performed by the decision engine 246 and the request may be allowedto be sent over the air to the server to satisfy the request. The blacklisted destinations or applications/clients (e.g., mobile applications)can be maintained locally in the local proxy (e.g., in the applicationprofile repository 242) or remotely (e.g., in the proxy server 325 oranother entity).

In one embodiment, the decision engine 246, for example, via the requestanalyzer 246 c, collects information about an application or clientrequest generated at the mobile device 250. The request information caninclude request characteristics information including, for example,request method. For example, the request method can indicate the type ofHTTP request generated by the mobile application or client. In oneembodiment, response to a request can be identified as cacheable orpotentially cacheable if the request method is a GET request or POSTrequest. Other types of requests (e.g., OPTIONS, HEAD, PUT, DELETE,TRACE, or CONNECT) may or may not be cached. In general, HTTP requestswith uncacheable request methods will not be cached.

Request characteristics information can further include informationregarding request size, for example. Responses to requests (e.g., HTTPrequests) with body size exceeding a certain size will not be cached.For example, cacheability can be determined if the information about therequest indicates that a request body size of the request does notexceed a certain size. In some instances, the maximum cacheable requestbody size can be set to 8092 bytes. In other instances, different valuesmay be used, dependent on network capacity or network operator specificsettings, for example.

In some instances, content from a given application server/contentprovider (e.g., the server/content provider 110 of FIG. 1B) isdetermined to be suitable for caching based on a set of criteria, forexample, criteria specifying time criticality of the content that isbeing requested from the content source. In one embodiment, the localproxy (e.g., the local proxy 175 or 275 of FIG. 1B and FIG. 2A) appliesa selection criteria to store the content from the host server which isrequested by an application as cached elements in a local cache on themobile device to satisfy subsequent requests made by the application.

The cache appropriateness decision engine 246, further based on detectedpatterns of requests sent from the mobile device 250 (e.g., by a mobileapplication or other types of clients on the device 250) and/or patternsof received responses, can detect predictability in requests and/orresponses. For example, the request characteristics informationcollected by the decision engine 246, (e.g., the request analyzer 246 c)can further include periodicity information between a request and otherrequests generated by a same client on the mobile device or otherrequests directed to the same host (e.g., with similar or sameidentifier parameters).

Periodicity can be detected, by the decision engine 246 or the requestanalyzer 246 c, when the request and the other requests generated by thesame client occur at a fixed rate or nearly fixed rate, or at a dynamicrate with some identifiable or partially or wholly reproducible changingpattern. If the requests are made with some identifiable pattern (e.g.,regular intervals, intervals having a detectable pattern, or trend(e.g., increasing, decreasing, constant, etc.) the timing predictor 246a can determine that the requests made by a given application on adevice is predictable and identify it to be potentially appropriate forcaching, at least from a timing standpoint.

An identifiable pattern or trend can generally include any applicationor client behavior which may be simulated either locally, for example,on the local proxy 275 on the mobile device 250 or simulated remotely,for example, by the proxy server 325 on the host 300, or a combinationof local and remote simulation to emulate application behavior.

In one embodiment, the decision engine 246, for example, via theresponse analyzer 246 d, can collect information about a response to anapplication or client request generated at the mobile device 250. Theresponse is typically received from a server or the host of theapplication (e.g., mobile application) or client which sent the requestat the mobile device 250. In some instances, the mobile client orapplication can be the mobile version of an application (e.g., socialnetworking, search, travel management, voicemail, contact manager,email) or a web site accessed via a web browser or via a desktop client.

For example, response characteristics information can include anindication of whether transfer encoding or chunked transfer encoding isused in sending the response. In some instances, responses to HTTPrequests with transfer encoding or chunked transfer encoding are notcached, and therefore are also removed from further analysis. Therationale here is that chunked responses are usually large andnon-optimal for caching, since the processing of these transactions maylikely slow down the overall performance. Therefore, in one embodiment,cacheability or potential for cacheability can be determined whentransfer encoding is not used in sending the response.

In addition, the response characteristics information can include anassociated status code of the response which can be identified by theresponse analyzer 246 d. In some instances, HTTP responses withuncacheable status codes are typically not cached. The response analyzer246 d can extract the status code from the response and determinewhether it matches a status code which is cacheable or uncacheable. Somecacheable status codes include by way of example: 200-OK, 301-Redirect,302-Found, 303-See other, 304-Not Modified, 307Temporary Redirect, or500-Internal server error. Some uncacheable status codes can include,for example, 403-Forbidden or 404-Not found.

In one embodiment, cacheability or potential for cacheability can bedetermined if the information about the response does not indicate anuncacheable status code or indicates a cacheable status code. If theresponse analyzer 246 d detects an uncacheable status code associatedwith a given response, the specific transaction (request/response pair)may be eliminated from further processing and determined to beuncacheable on a temporary basis, a semi-permanent, or a permanentbasis. If the status code indicates cacheability, the transaction (e.g.,request and/or response pair) may be subject to further processing andanalysis to confirm cacheability, as shown in the example flow charts ofFIG. 9-13.

Response characteristics information can also include response sizeinformation. In general, responses can be cached locally at the mobiledevice 250 if the responses do not exceed a certain size. In someinstances, the default maximum cached response size is set to 128 KB. Inother instances, the max cacheable response size may be different and/ordynamically adjusted based on operating conditions, network conditions,network capacity, user preferences, network operator requirements, orother application-specific, user specific, and/or device-specificreasons. In one embodiment, the response analyzer 246 d can identify thesize of the response, and cacheability or potential for cacheability canbe determined if a given threshold or max value is not exceeded by theresponse size.

Furthermore, response characteristics information can include responsebody information for the response to the request and other response toother requests generated by a same client on the mobile device, ordirected to a same content host or application server. The response bodyinformation for the response and the other responses can be compared,for example, by the response analyzer 246 d, to prevent the caching ofdynamic content (or responses with content that changes frequently andcannot be efficiently served with cache entries, such as financial data,stock quotes, news feeds, real-time sporting event activities, etc.),such as content that would no longer be relevant or up-to-date if servedfrom cached entries.

The cache appropriateness decision engine 246 (e.g., the contentpredictor 246 b) can definitively identify repeatability or identifyindications of repeatability, potential repeatability, or predictabilityin responses received from a content source (e.g., the contenthost/application server 110 shown in the example of FIG. 1A-B).Repeatability can be detected by, for example, tracking at least tworesponses received from the content source and determines if the tworesponses are the same. For example, cacheability can be determined, bythe response analyzer 246 d, if the response body information for theresponse and the other responses sent by the same mobile client ordirected to the same host/server are same or substantially the same. Thetwo responses may or may not be responses sent in response toconsecutive requests. In one embodiment, hash values of the responsesreceived for requests from a given application are used to determinerepeatability of content (with or without heuristics) for theapplication in general and/or for the specific request. Additional sameresponses may be required for some applications or under certaincircumstances.

Repeatability in received content need not be 100% ascertained. Forexample, responses can be determined to be repeatable if a certainnumber or a certain percentage of responses are the same, or similar.The certain number or certain percentage of same/similar responses canbe tracked over a select period of time, set by default or set based onthe application generating the requests (e.g., whether the applicationis highly dynamic with constant updates or less dynamic with infrequentupdates). Any indicated predictability or repeatability, or possiblerepeatability, can be utilized by the distributed system in cachingcontent to be provided to a requesting application or client on themobile device 250.

In one embodiment, for a long poll type request, the local proxy 175 canbegin to cache responses on a third request when the response delaytimes for the first two responses are the same, substantially the same,or detected to be increasing in intervals. In general, the receivedresponses for the first two responses should be the same, and uponverifying that the third response received for the third request is thesame (e.g., if R0=R1=R2), the third response can be locally cached onthe mobile device. Less or more same responses may be required to begincaching, depending on the type of application, type of data, type ofcontent, user preferences, or carrier/network operator specifications.

Increasing response delays with same responses for long polls canindicate a hunting period (e.g., a period in which theapplication/client on the mobile device is seeking the longest timebetween a request and response that a given network will allow, a timingdiagram showing timing characteristics is illustrated in FIG. 8), asdetected by the long poll hunting detector 238 c of the applicationbehavior detector 236.

An example can be described below using T0, T1, T2, where T indicatesthe delay time between when a request is sent and when a response (e.g.,the response header) is detected/received for consecutive requests:

T0=Response0(t)−Request0(t)=180 s. (+/−tolerance)

T1=Response1(t)−Request1(t)=240 s. (+/−tolerance)

T2=Response2(t)−Request2(t)=500 s. (+/−tolerance)

In the example timing sequence shown above, T0<T1<T2, this may indicatea hunting pattern for a long poll when network timeout has not yet beenreached or exceeded. Furthermore, if the responses R0, R1, and R2received for the three requests are the same, R2 can be cached. In thisexample, R2 is cached during the long poll hunting period withoutwaiting for the long poll to settle, thus expediting response caching(e.g., this is optional accelerated caching behavior which can beimplemented for all or select applications).

As such, the local proxy 275 can specify information that can beextracted from the timing sequence shown above (e.g., polling schedule,polling interval, polling type) to the proxy server and begin cachingand to request the proxy server to begin polling and monitoring thesource (e.g., using any of T0, T1, T2 as polling intervals but typicallyT2, or the largest detected interval without timing out, and for whichresponses from the source is received will be sent to the proxy server325 of FIG. 3A for use in polling the content source (e.g., applicationserver/service provider 310)).

However, if the time intervals are detected to be getting shorter, theapplication (e.g., mobile application)/client may still be hunting for atime interval for which a response can be reliably received from thecontent source (e.g., application/server server/provider 110 or 310),and as such caching typically should not begin until therequest/response intervals indicate the same time interval or anincreasing time interval, for example, for a long poll type request.

An example of handling a detected decreasing delay can be describedbelow using T0, T1, T2, T3, and T4 where T indicates the delay timebetween when a request is sent and when a response (e.g., the responseheader) is detected/received for consecutive requests:

T0=Response0(t)−Request0(t)=160 s. (+/−tolerance)

T1=Response1(t)−Request1(t)=240 s. (+/−tolerance)

T2=Response2(t)−Request2(t)=500 s. (+/−tolerance)

T3=Time out at 700 s. (+/−tolerance)

T4=Response4(t)−Request4(t)=600 (+/−tolerance)

If a pattern for response delays T1<T2<T3>T4 is detected, as shown inthe above timing sequence (e.g., detected by the long poll huntingdetector 238 c of the application behavior detector 236), it can bedetermined that T3 likely exceeded the network time out during a longpoll hunting period. In Request 3, a response likely was not receivedsince the connection was terminated by the network, application, server,or other reason before a response was sent or available. On Request 4(after T4), if a response (e.g., Response 4) is detected or received,the local proxy 275 can then use the response for caching (if thecontent repeatability condition is met). The local proxy can also use T4as the poll interval in the polling schedule set for the proxy server tomonitor/poll the content source.

Note that the above description shows that caching can begin while longpolls are in hunting mode in the event of detecting increasing responsedelays, as long as responses are received and not timed out for a givenrequest. This can be referred to as the optional accelerated cachingduring long poll hunting. Caching can also begin after the hunting mode(e.g., after the poll requests have settled to a constant or nearconstant delay value) has completed. Note that hunting may or may notoccur for long polls and when hunting occurs; the proxy 275 cangenerally detect this and determine whether to begin to cache during thehunting period (increasing intervals with same responses) or wait untilthe hunt settles to a stable value.

In one embodiment, the timing predictor 246 a of the cacheappropriateness decision engine 246 can track timing of responsesreceived from outgoing requests from an application (e.g., mobileapplication) or client to detect any identifiable patterns which can bepartially wholly reproducible, such that locally cached responses can beprovided to the requesting client on the mobile device 250 in a mannerthat simulates content source (e.g., application server/content provider110 or 310) behavior. For example, the manner in which (e.g., from atiming standpoint) responses or content would be delivered to therequesting application/client on the device 250. This ensurespreservation of user experience when responses to application or mobileclient requests are served from a local and/or remote cache instead ofbeing retrieved/received directly from the content source (e.g.,application, content provider 110 or 310).

In one embodiment, the decision engine 246 or the timing predictor 246 adetermines the timing characteristics a given application (e.g., mobileapplication) or client from, for example, the request/response trackingengine 238 b and/or the application profile generator 239 (e.g., theresponse delay interval tracker 239 a). Using the timingcharacteristics, the timing predictor 246 a determines whether thecontent received in response to the requests are suitable or arepotentially suitable for caching. For example, poll request intervalsbetween two consecutive requests from a given application can be used todetermine whether request intervals are repeatable (e.g., constant, nearconstant, increasing with a pattern, decreasing with a pattern, etc.)and can be predicted and thus reproduced at least some of the timeseither exactly or approximated within a tolerance level.

In some instances, the timing characteristics of a given request typefor a specific application, for multiple requests of an application, orfor multiple applications can be stored in the application profilerepository 242. The application profile repository 242 can generallystore any type of information or metadata regarding applicationrequest/response characteristics including timing patterns, timingrepeatability, content repeatability, etc.

The application profile repository 242 can also store metadataindicating the type of request used by a given application (e.g., longpolls, long-held HTTP requests, HTTP streaming, push, COMET push, etc.)Application profiles indicating request type by applications can be usedwhen subsequent same/similar requests are detected, or when requests aredetected from an application which has already been categorized. In thismanner, timing characteristics for the given request type or forrequests of a specific application which has been tracked and/oranalyzed, need not be reanalyzed.

Application profiles can be associated with a time-to-live (e.g., or adefault expiration time). The use of an expiration time for applicationprofiles, or for various aspects of an application or request's profilecan be used on a case by case basis. The time-to-live or actualexpiration time of application profile entries can be set to a defaultvalue or determined individually, or a combination thereof. Applicationprofiles can also be specific to wireless networks, physical networks,network operators, or specific carriers.

One embodiment includes an application blacklist manager 201. Theapplication blacklist manager 201 can be coupled to the applicationcache policy repository 243 and can be partially or wholly internal tolocal proxy or the caching policy manager 245. Similarly, the blacklistmanager 201 can be partially or wholly internal to local proxy or theapplication behavior detector 236. The blacklist manager 201 canaggregate, track, update, manage, adjust, or dynamically monitor a listof destinations of servers/host that are ‘blacklisted,’ or identified asnot cached, on a permanent or temporary basis. The blacklist ofdestinations, when identified in a request, can potentially be used toallow the request to be sent over the (cellular) network for servicing.Additional processing on the request may not be performed since it isdetected to be directed to a blacklisted destination.

Blacklisted destinations can be identified in the application cachepolicy repository 243 by address identifiers including specific URIs orpatterns of identifiers including URI patterns. In general, blacklisteddestinations can be set by or modified for any reason by any partyincluding the user (owner/user of mobile device 250), operatingsystem/mobile platform of device 250, the destination itself, networkoperator (of cellular network), Internet service provider, other thirdparties, or according to a list of destinations for applications knownto be uncacheable/not suited for caching. Some entries in theblacklisted destinations may include destinations aggregated based onthe analysis or processing performed by the local proxy (e.g., cacheappropriateness decision engine 246).

For example, applications or mobile clients on the mobile device forwhich responses have been identified as non-suitable for caching can beadded to the blacklist. Their corresponding hosts/servers may be addedin addition to or in lieu of an identification of the requestingapplication/client on the mobile device 250. Some or all of such clientsidentified by the proxy system can be added to the blacklist. Forexample, for all application clients or applications that aretemporarily identified as not being suitable for caching, only thosewith certain detected characteristics (based on timing, periodicity,frequency of response content change, content predictability, size,etc.) can be blacklisted.

The blacklisted entries may include a list of requesting applications orrequesting clients on the mobile device (rather than destinations) suchthat, when a request is detected from a given application or givenclient, it may be sent through the network for a response, sinceresponses for blacklisted clients/applications are in most circumstancesnot cached.

A given application profile may also be treated or processed differently(e.g., different behavior of the local proxy 275 and the remote proxy325) depending on the mobile account associated with a mobile devicefrom which the application is being accessed. For example, a higherpaying account, or a premier account may allow more frequent access ofthe wireless network or higher bandwidth allowance thus affecting thecaching policies implemented between the local proxy 275 and proxyserver 325 with an emphasis on better performance compared toconservation of resources. A given application profile may also betreated or processed differently under different wireless networkconditions (e.g., based on congestion or network outage, etc.).

Note that cache appropriateness can be determined, tracked, and managedfor multiple clients or applications on the mobile device 250. Cacheappropriateness can also be determined for different requests or requesttypes initiated by a given client or application on the mobile device250. The caching policy manager 245, along with the timing predictor 246a and/or the content predictor 246 b which heuristically determines orestimates predictability or potential predictability, can track, manageand store cacheability information for various application or variousrequests for a given application. Cacheability information may alsoinclude conditions (e.g., an application can be cached at certain timesof the day, or certain days of the week, or certain requests of a givenapplication can be cached, or all requests with a given destinationaddress can be cached) under which caching is appropriate which can bedetermined and/or tracked by the cache appropriateness decision engine246 and stored and/or updated when appropriate in the application cachepolicy repository 243 coupled to the cache appropriateness decisionengine 246.

The information in the application cache policy repository 243 regardingcacheability of requests, applications, and/or associated conditions canbe used later on when same requests are detected. In this manner, thedecision engine 246 and/or the timing and content predictors 246 a/bneed not track and reanalyze request/response timing and contentcharacteristics to make an assessment regarding cacheability. Inaddition, the cacheability information can in some instances be sharedwith local proxies of other mobile devices by way of directcommunication or via the host server (e.g., proxy server 325 of hostserver 300).

For example, cacheability information detected by the local proxy 275 onvarious mobile devices can be sent to a remote host server or a proxyserver 325 on the host server (e.g., host server 300 or proxy server 325shown in the example of FIG. 3A, host 100 and proxy server 125 in theexample of FIG. 1A-B). The remote host or proxy server can thendistribute the information regarding application-specific,request-specific cacheability information and/or any associatedconditions to various mobile devices or their local proxies in awireless network or across multiple wireless networks (same serviceprovider or multiple wireless service providers) for their use.

In general, the selection criteria for caching can further include, byway of example but not limitation, the state of the mobile deviceindicating whether the mobile device is active or inactive, networkconditions, and/or radio coverage statistics. The cache appropriatenessdecision engine 246 can in any one or any combination of the criteria,and in any order, identifying sources for which caching may be suitable.

Once application servers/content providers having identified or detectedcontent that is potentially suitable for local caching on the mobiledevice 250, the cache policy manager 245 can proceed to cache theassociated content received from the identified sources by storingcontent received from the content source as cache elements in a localcache (e.g., local cache 185 or 285 shown in the examples of FIG. 1B andFIG. 2A, respectively) on the mobile device 250.

The response can be stored in the cache 285 (e.g., also referred as thelocal cache) as a cache entry. In addition to the response to a request,the cached entry can include response metadata having additionalinformation regarding caching of the response. The metadata may begenerated by the metadata generator 203 and can include, for example,timing data such as the access time of the cache entry or creation timeof the cache entry. Metadata can include additional information, such asany information suited for use in determining whether the responsestored as the cached entry is used to satisfy the subsequent response.For example, metadata information can further include, request timinghistory (e.g., including request time, request start time, request endtime), hash of the request and/or response, time intervals or changes intime intervals, etc.

The cache entry is typically stored in the cache 285 in association witha time-to-live (TTL), which for example may be assigned or determined bythe TTL manager 244 a of the cache invalidator 244. The time-to-live ofa cache entry is the amount of time the entry is persisted in the cache285 regardless of whether the response is still valid or relevant for agiven request or client/application on the mobile device 250. Forexample, if the time-to-live of a given cache entry is set to 12 hours,the cache entry is purged, removed, or otherwise indicated as havingexceeded the time-to-live, even if the response body contained in thecache entry is still current and applicable for the associated request.

A default time-to-live can be automatically used for all entries unlessotherwise specified (e.g., by the TTL manager 244 a), or each cacheentry can be created with its individual TTL (e.g., determined by theTTL manager 244 a based on various dynamic or static criteria). Notethat each entry can have a single time-to-live associated with both theresponse data and any associated metadata. In some instances, theassociated metadata may have a different time-to-live (e.g., a longertime-to-live) than the response data. Examples of representations of adata model of a cache entry are illustrated in FIG. 24 and FIG. 25.

The content source having content for caching can, in addition or inalternate, be identified to a proxy server (e.g., proxy server 125 or325 shown in the examples of FIG. 1B and FIG. 3A, respectively) remotefrom and in wireless communication with the mobile device 250 such thatthe proxy server can monitor the content source (e.g., applicationserver/content provider 110) for new or changed data. Similarly, thelocal proxy (e.g., the local proxy 175 or 275 of FIG. 1B and FIG. 2A,respectively) can identify to the proxy server that content receivedfrom a specific application server/content provider is being stored ascached elements in the local cache 285.

Once content has been locally cached, the cache policy manager 245, uponreceiving future polling requests to contact the applicationserver/content host (e.g., 110 or 310), can retrieve the cached elementsfrom the local cache to respond to the polling request made at themobile device 250 such that a radio of the mobile device is notactivated to service the polling request. For example, the cache look-upengine 205 can query the cache 285 to identify the response to be servedto a response. The response can be served from the cache in response toidentifying a matching cache entry and also using any metadata storedwith the response in the cache entry. The cache entries can be queriedby the cache look-up engine using a URI of the request or another typeof identifier (e.g., via the ID or URI filter 205 a). The cache-lookupengine 205 can further use the metadata (e.g., extract any timinginformation or other relevant information) stored with the matchingcache entry to determine whether response is still suited for use inbeing served to a current request.

Note that the cache-look-up can be performed by the engine 205 using oneor more of various multiple strategies. In one embodiment, multiplecook-up strategies can be executed sequentially on each entry store dinthe cache 285, until at least one strategy identifies a matching cacheentry. The strategy employed to performing cache look-up can include astrict matching criteria or a matching criteria which allows fornon-matching parameters.

For example, the look-up engine 205 can perform a strict matchingstrategy which searches for an exact match between an identifier (e.g.,a URI for a host or resource) referenced in a present request for whichthe proxy is attempting to identify a cache entry and an identifierstored with the cache entries. In the case where identifiers includeURIs or URLs, the matching algorithm for strict matching will search fora cache entry where all the parameters in the URLs match. For example:

Example 1.

1. Cache contains entry for http://test.com/products/

2. Request is being made to URI http://test.com/products/

Strict strategy will find a match, since both URIs are same.

Example 2

1. Cache contains entry for http://test.com/products/?query=all

2. Request is being made to URI http://test.com/products/?query=sub

Under the strict strategy outlined above, a match will not be foundsince the URIs differ in the query parameter.

In another example strategy, the look-up engine 205 looks for a cacheentry with an identifier that partially matches the identifierreferences in a present request for which the proxy is attempting toidentify a matching cache entry. For example, the look-up engine 205 maylook for a cache entry with an identifier which differs from the requestidentifier by a query parameter value. In utilizing this strategy, thelook-up engine 205 can collect information collected for multipleprevious requests (e.g., a list of arbitrary parameters in anidentifier) to be later checked with the detected arbitrary parameter inthe current request. For example, in the case where cache entries arestored with URI or URL identifiers, the look-up engine searches for acache entry with a URI differing by a query parameter. If found, theengine 205 can examine the cache entry for information collected duringprevious requests (e.g. a list of arbitrary parameters) and checkedwhether the arbitrary parameter detected in or extracted from thecurrent URI/URL belongs to the arbitrary parameters list.

Example 1.

1. Cache contains entry for http://test.com/products/?query=all, wherequery is marked as arbitrary.

2. Request is being made to URI http://text.com/products/?query=sub

Match will be found, since query parameter is marked as arbitrary.

Example 2

1. Cache contains entry for http://test.com/products/?query=all, wherequery is marked as arbitrary.

2. Request is being made to URIhttp://test.com/products/?query=sub&sort=asc

Match will not be found, since current request contains sort parameterwhich is not marked as arbitrary in the cache entry.

Additional strategies for detecting cache hit may be employed. Thesestrategies can be implemented singly or in any combination thereof. Acache-hit can be determined when any one of these strategies determinesa match. A cache miss may be indicated when the look-up engine 205determines that the requested data cannot be served from the cache 285,for any reason. For example, a cache miss may be determined when nocache entries are identified for any or all utilized look-up strategies.

Cache miss may also be determined when a matching cache entry exists butdetermined to be invalid or irrelevant for the current request. Forexample, the look-up engine 205 may further analyze metadata (e.g.,which may include timing data of the cache entry) associated with thematching cache entry to determine whether it is still suitable for usein responding to the present request.

When the look-up engine 205 has identified a cache hit (e.g., an eventindicating that the requested data can be served from the cache), thestored response in the matching cache entry can be served from the cacheto satisfy the request of an application/client.

By servicing requests using cache entries stored in cache 285, networkbandwidth and other resources need not be used to request/receive pollresponses which may have not changed from a response that has alreadybeen received at the mobile device 250. Such servicing and fulfillingapplication (e.g., mobile application) requests locally via cacheentries in the local cache 285 allows for more efficient resource andmobile network traffic utilization and management since the request neednot be sent over the wireless network further consuming bandwidth. Ingeneral, the cache 285 can be persisted between power on/off of themobile device 250, and persisted across application/client refreshes andrestarts.

For example, the local proxy 275, upon receipt of an outgoing requestfrom its mobile device 250 or from an application or other type ofclient on the mobile device 250, can intercept the request and determinewhether a cached response is available in the local cache 285 of themobile device 250. If so, the outgoing request is responded to by thelocal proxy 275 using the cached response on the cache of the mobiledevice. As such, the outgoing request can be filled or satisfied withouta need to send the outgoing request over the wireless network, thusconserving network resources and battery consumption.

In one embodiment, the responding to the requesting application/clienton the device 250 is timed to correspond to a manner in which thecontent server would have responded to the outgoing request over apersistent connection (e.g., over the persistent connection, orlong-held HTTP connection, long poll type connection, that would havebeen established absent interception by the local proxy). The timing ofthe response can be emulated or simulated by the local proxy 275 topreserve application behavior such that end user experience is notaffected, or minimally affected by serving stored content from the localcache 285 rather than fresh content received from the intended contentsource (e.g., content host/application server 110 of FIG. 1A-B). Thetiming can be replicated exactly or estimated within a toleranceparameter, which may go unnoticed by the user or treated similarly bythe application so as to not cause operation issues.

For example, the outgoing request can be a request for a persistentconnection intended for the content server (e.g., applicationserver/content provider of examples of FIG. 1A-1B). In a persistentconnection (e.g., long poll, COMET-style push or any other pushsimulation in asynchronous HTTP requests, long-held HTTP request, HTTPstreaming, or others) with a content source (server), the connection isheld for some time after a request is sent. The connection can typicallybe persisted between the mobile device and the server until content isavailable at the server to be sent to the mobile device. Thus, theretypically can be some delay in time between when a long poll request issent and when a response is received from the content source. If aresponse is not provided by the content source for a certain amount oftime, the connection may also terminate due to network reasons (e.g.,socket closure) if a response is not sent.

Thus, to emulate a response from a content server sent over a persistentconnection (e.g., a long poll style connection), the manner of responseof the content server can be simulated by allowing a time interval toelapse before responding to the outgoing request with the cachedresponse. The length of the time interval can be determined on a requestby request basis or on an application by application (client by clientbasis), for example.

In one embodiment, the time interval is determined based on requestcharacteristics (e.g., timing characteristics) of an application on themobile device from which the outgoing request originates. For example,poll request intervals (e.g., which can be tracked, detected, anddetermined by the long poll detector 238 a of the poll interval detector238) can be used to determine the time interval to wait beforeresponding to a request with a local cache entry and managed by theresponse scheduler 249 a.

One embodiment of the cache policy manager 245 includes a poll schedulegenerator 247 which can generate a polling schedule for one or moreapplications on the mobile device 250. The polling schedule can specifya polling interval that can be employed by an entity which is physicallydistinct and/or separate from the mobile device 250 in monitoring thecontent source for one or more applications (such that cached responsescan be verified periodically by polling a host server (host server 110or 310) to which the request is directed) on behalf of the mobiledevice. One example of such an external entity which can monitor thecontent at the source for the mobile device 250 is a proxy server (e.g.,proxy server 125 or 325 shown in the examples of FIG. 1B and FIG. 3A-C).

The polling schedule (e.g., including a rate/frequency of polling) canbe determined, for example, based on the interval between the pollingrequests directed to the content source from the mobile device. Thepolling schedule or rate of polling may be determined at the mobiledevice 250 (by the local proxy). In one embodiment, the poll intervaldetector 238 of the application behavior detector 236 can monitorpolling requests directed to a content source from the mobile device 250in order to determine an interval between the polling requests made fromany or all application (e.g., mobile application).

For example, the poll interval detector 238 can track requests andresponses for applications or clients on the device 250. In oneembodiment, consecutive requests are tracked prior to detection of anoutgoing request initiated from the application (e.g., mobileapplication) on the mobile device 250 by the same mobile client orapplication (e.g., mobile application). The polling rate can bedetermined using request information collected for the request for whichthe response is cached. In one embodiment, the rate is determined fromaverages of time intervals between previous requests generated by thesame client which generated the request. For example, a first intervalmay be computed between the current request and a previous request, anda second interval can be computed between the two previous requests. Thepolling rate can be set from the average of the first interval and thesecond interval and sent to the proxy server in setting up the cachingstrategy.

Alternate intervals may be computed in generating an average; forexample, multiple previous requests in addition to two previous requestsmay be used, and more than two intervals may be used in computing anaverage. In general, in computing intervals, a given request need nothave resulted in a response to be received from the host server/contentsource in order to use it for interval computation. In other words, thetiming characteristics of a given request may be used in intervalcomputation, as long as the request has been detected, even if therequest failed in sending, or if the response retrieval failed.

One embodiment of the poll schedule generator 247 includes a scheduleupdate engine 247 a and/or a time adjustment engine 247 b. The scheduleupdate engine 247 a can determine a need to update a rate or pollinginterval with which a given application server/content host from apreviously set value, based on a detected interval change in the actualrequests generated from a client or application (e.g., mobileapplication) on the mobile device 250.

For example, a request for which a monitoring rate was determined maynow be sent from the application (e.g., mobile application) or client ata different request interval. The scheduled update engine 247 a candetermine the updated polling interval of the actual requests andgenerate a new rate, different from the previously set rate to poll thehost at on behalf of the mobile device 250. The updated polling rate canbe communicated to the remote proxy (proxy server 325) over the cellularnetwork for the remote proxy to monitor the given host. In someinstances, the updated polling rate may be determined at the remoteproxy or remote entity which monitors the host.

In one embodiment, the time adjustment engine 247 b can further optimizethe poll schedule generated to monitor the application server/contentsource (110 or 310). For example, the time adjustment engine 247 b canoptionally specify a time to start polling to the proxy server. Forexample, in addition to setting the polling interval at which the proxyserver is to monitor the application, server/content host can alsospecify the time at which an actual request was generated at the mobileclient/application.

However, in some cases, due to inherent transmission delay or addednetwork delays or other types of latencies, the remote proxy serverreceives the poll setup from the local proxy with some delay (e.g., afew minutes, or a few seconds). This has the effect of detectingresponse change at the source after a request is generated by the mobileclient/application causing the invalidate of the cached response tooccur after it has once again been served to the application after theresponse is no longer current or valid. This discrepancy is furtherillustrated diagrammatically in the data timing diagram of FIG. 21.

To resolve this non-optimal result of serving the out-dated content onceagain before invalidating it, the time adjustment engine 247 b canspecify the time (t0) at which polling should begin in addition to therate, where the specified initial time t0 can be specified to the proxyserver 325 as a time that is less than the actual time when the requestwas generated by the mobile app/client. This way, the server polls theresource slightly before the generation of an actual request by themobile client such that any content change can be detected prior to anactual application request. This prevents invalid or irrelevantout-dated content/response from being served once again before freshcontent is served.

In one embodiment, an outgoing request from a mobile device 250 isdetected to be for a persistent connection (e.g., a long poll, COMETstyle push, and long-held (HTTP) request) based on timingcharacteristics of prior requests from the same application or client onthe mobile device 250. For example, requests and/or correspondingresponses can be tracked by the request/response tracking engine 238 bof the long poll detector 238 a of the poll interval detector 238.

The timing characteristics of the consecutive requests can be determinedto set up a polling schedule for the application or client. The pollingschedule can be used to monitor the content source (contentsource/application server) for content changes such that cached contentstored on the local cache in the mobile device 250 can be appropriatelymanaged (e.g., updated or discarded). In one embodiment, the timingcharacteristics can include, for example, a response delay time (‘D’)and/or an idle time (‘IT’).

The response delay time and idle time typical of a long poll areillustrated in the timing diagram shown below and also described furtherin detail with references to FIG. 17A-B. In one embodiment, theresponse/request tracking engine 238 b can track requests and responsesto determine, compute, and/or estimate, the timing diagrams forapplicant or client requests.

For example, the response/request tracking engine 238 b detects a firstrequest (Request 0) initiated by a client on the mobile device and asecond request (Request 1) initiated by the client on the mobile deviceafter a response is received at the mobile device responsive to thefirst request. The second request is one that is subsequent to the firstrequest. The relationship between requests can be seen in the timingdiagrams of FIG. 17A-B.

In one embodiment, the response/request tracking engine 238 b can trackrequests and responses to determine, compute, and/or estimate the timingdiagrams for applicant or client requests. The response/request trackingengine 238 b can detect a first request initiated by a client on themobile device and a second request initiated by the client on the mobiledevice after a response is received at the mobile device responsive tothe first request. The second request is one that is subsequent to thefirst request.

The response/request tracking engine 238 b further determines relativetimings between the first, second requests, and the response received inresponse to the first request. In general, the relative timings can beused by the long poll detector 238 a to determine whether requestsgenerated by the application are long poll requests.

Note that in general, the first and second requests that are used by theresponse/request tracking engine 238 b in computing the relative timingsare selected for use after a long poll hunting period has settled or inthe event when long poll hunting does not occur. Timing characteristicsthat are typical of a long poll hunting period is illustrated in theexample of FIG. 8 and can be, for example, detected by the long pollhunting detector 238 c. In other words, the requests tracked by theresponse/request tracking engine 238 b and used for determining whethera given request is a long poll occurs after the long poll has settled(e.g., shown in 810 of FIG. 8 after the hunting mode 805 has completed).

In one embodiment, the long poll hunting detector 238 c can identify ordetect hunting mode, by identifying increasing request intervals (e.g.,increasing delays). The long poll hunting detector 238 a can also detecthunting mode by detecting increasing request intervals, followed by arequest with no response (e.g., connection timed out), or by detectingincreasing request intervals followed by a decrease in the interval. Inaddition, the long poll hunting detector 238 c can apply a filter valueor a threshold value to request-response time delay value (e.g., anabsolute value) above which the detected delay can be considered to be along poll request-response delay. The filter value can be any suitablevalue characteristic of long polls and/or network conditions (e.g., 2 s,5 s, 10 s, 15 s, 20 s., etc.) and can be used as a filter or thresholdvalue.

The response delay time (‘D’) refers to the start time to receive aresponse after a request has been sent and the idle refers to time tosend a subsequent request after the response has been received. In oneembodiment, the outgoing request is detected to be for a persistentconnection based on a comparison (e.g., performed by the tracking engine238 b) of the response delay time relative (‘D’) or average of (‘D’)(e.g., any average over any period of time) to the idle time (‘IT’), forexample, by the long poll detector 238 a. The number of averages usedcan be fixed, dynamically adjusted, or changed over a longer period oftime. For example, the requests initiated by the client are determinedto be long poll requests if the response delay time interval is greaterthan the idle time interval (D>IT or D>>IT). In one embodiment, thetracking engine 238 b of the long poll detector computes, determines, orestimates the response delay time interval as the amount of time elapsedbetween time of the first request and initial detection or full receiptof the response. In one embodiment, a request is detected to be for apersistent connection when the idle time (‘IT’) is short sincepersistent connections, established in response to long poll requests orlong poll HTTP requests for example, can also be characterized indetecting immediate or near-immediate issuance of a subsequent requestafter receipt of a response to a previous request (e.g., IT˜0). As such,the idle time (‘IT’) can also be used to detect such immediate ornear-immediate re-request to identify long poll requests. The absoluteor relative timings determined by the tracking engine 238 b are used todetermine whether the second request is immediately or near-immediatelyre-requested after the response to the first request is received. Forexample, a request may be categorized as a long poll request ifD+RT+IT˜D+RT since IT is small for this to hold true. IT may bedetermined to be small if it is less than a threshold value. Note thatthe threshold value could be fixed or calculated over a limited timeperiod (a session, a day, a month, etc.), or calculated over a longertime period (e.g., several months or the life of the analysis). Forexample, for every request, the average IT can be determined, and thethreshold can be determined using this average IT (e.g., the average ITless a certain percentage may be used as the threshold). This can allowthe threshold to automatically adapt over time to network conditions andchanges in server capability, resource availability or server response.A fixed threshold can take upon any value including by way of examplebut not limitation (e.g., 1 s. 2 s. 3 s. . . . etc.).

In one embodiment, the long poll detector 238 a can compare the relativetimings (e.g., determined by the tracker engine 238 b) torequest-response timing characteristics for other applications todetermine whether the requests of the application are long pollrequests. For example, the requests initiated by a client or applicationcan be determined to be long poll requests if the response delayinterval time (‘D’) or the average response delay interval time (e.g.,averaged over x number of requests or any number of delay interval timesaveraged over x amount of time) is greater than a threshold value.

The threshold value can be determined using response delay intervaltimes for requests generated by other clients, for example by therequest/response tracking engine 238 b and/or by the application profilegenerator 239 (e.g., the response delay interval tracker 239 a). Theother clients may reside on the same mobile device and the thresholdvalue is determined locally by components on the mobile device. Thethreshold value can be determined for all requests over all resourcesserver over all networks, for example. The threshold value can be set toa specific constant value (e.g., 30 seconds, for example) to be used forall requests, or any request which does not have an applicable thresholdvalue (e.g., long poll is detected if D>30 seconds).

In some instances, the other clients reside on different mobile devicesand the threshold can be determined by a proxy server (e.g., proxyserver 325 of the host 300 shown in the example of FIG. 3A-B) which isexternal to the mobile device and able to communicate over a wirelessnetwork with the multiple different mobile devices, as will be furtherdescribed with reference to FIG. 3B.

In one embodiment, the cache policy manager 245 sends the pollingschedule to the proxy server (e.g., proxy server 125 or 325 shown in theexamples of FIG. 1B and FIG. 3A) and can be used by the proxy server inmonitoring the content source, for example, for changed or new content(updated response different from the cached response associated with arequest or application). A polling schedule sent to the proxy caninclude multiple timing parameters including but not limited to interval(time from request 1 to request 2) or a time out interval (time to waitfor response, used in long polls, for example). Referring to the timingdiagram of a request/response timing sequence shown in the example ofFIG. 17A-B, the timing intervals ‘RI’, ‘D’, ‘RT’, and/or ‘IT’, or somestatistical manipulation of the above values (e.g., average, standarddeviation, etc.) may all or in part be sent to the proxy server.

For example, in the case when the local proxy 275 detects a long poll,the various timing intervals in a request/response timing sequence(e.g., ‘D’, ‘RT’, and/or ‘IT’) can be sent to the proxy server 325 foruse in polling the content source (e.g., application server/content host110). The local proxy 275 can also identify to the proxy server 325 thata given application or request to be monitored is a long poll request(e.g., instructing the proxy server to set a ‘long poll flag’, forexample). In addition, the proxy server uses the various timingintervals to determine when to send keep-alive indications on behalf ofmobile devices.

The local cache invalidator 244 of the caching policy manager 245 caninvalidate cache elements in the local cache (e.g., cache 185 or 285)when new or changed data (e.g., updated response) is detected from theapplication server/content source for a given request. The cachedresponse can be determined to be invalid for the outgoing request basedon a notification received from the proxy server (e.g., proxy 325 or thehost server 300). The source which provides responses to requests of themobile client can be monitored to determine relevancy of the cachedresponse stored in the cache of the mobile device 250 for the request.For example, the cache invalidator 244 can further remove/delete thecached response from the cache of the mobile device when the cachedresponse is no longer valid for a given request or a given application.

In one embodiment, the cached response is removed from the cache afterit is provided once again to an application which generated the outgoingrequest after determining that the cached response is no longer valid.The cached response can be provided again without waiting for the timeinterval or provided again after waiting for a time interval (e.g., thetime interval determined to be specific to emulate the response delay ina long poll). In one embodiment, the time interval is the response delay‘D’ or an average value of the response delay ‘D’ over two or morevalues.

The new or changed data can be, for example, detected by the proxyserver (e.g., proxy server 125 or 325 shown in the examples of FIG. 1Band FIG. 3A). When a cache entry for a given request/poll has beeninvalidated, the use of the radio on the mobile device 250 can beenabled (e.g., by the local proxy 275 or the cache policy manager 245)to satisfy the subsequent polling requests, as further described withreference to the interaction diagram of FIG. 4B.

One embodiment of the cache policy manager 245 includes a cache orconnect selection engine 249 which can decide whether to use a locallycached entry to satisfy a poll/content request generated at the mobiledevice 250 by an application or widget. For example, the local proxy 275or the cache policy manger 245 can intercept a polling request, made byan application (e.g., mobile application) on the mobile device, tocontact the application server/content provider. The selection engine249 can determine whether the content received for the interceptedrequest has been locally stored as cache elements for deciding whetherthe radio of the mobile device needs to be activated to satisfy therequest made by the application (e.g., mobile application) and alsodetermine whether the cached response is still valid for the outgoingrequest prior to responding to the outgoing request using the cachedresponse.

In one embodiment, the local proxy 275, in response to determining thatrelevant cached content exists and is still valid, can retrieve thecached elements from the local cache to provide a response to theapplication (e.g., mobile application) which made the polling requestsuch that a radio of the mobile device is not activated to provide theresponse to the application (e.g., mobile application). In general, thelocal proxy 275 continues to provide the cached response each time theoutgoing request is received until the updated response different fromthe cached response is detected.

When it is determined that the cached response is no longer valid, a newrequest for a given request is transmitted over the wireless network foran updated response. The request can be transmitted to the applicationserver/content provider (e.g., server/host 110) or the proxy server onthe host server (e.g., proxy 325 on the host 300) for a new and updatedresponse. In one embodiment the cached response can be provided again asa response to the outgoing request if a new response is not receivedwithin the time interval, prior to removal of the cached response fromthe cache on the mobile device.

FIG. 2C depicts a block diagram illustrating another example ofcomponents in the application behavior detector 236 and the cachingpolicy manager 245 in the local proxy 275 on the client-side of thedistributed proxy system shown in the example of FIG. 2A. Theillustrated application behavior detector 236 and the caching policymanager 245 can, for example, enable the local proxy 275 to detect cachedefeat and perform caching of content addressed by identifiers intendedto defeat cache, and can further include or be coupled to components(e.g., heartbeat manager 267) for managing keep-alive messages.

In one embodiment, the caching policy manager 245 includes a cachedefeat resolution engine 221, an identifier formalizer 211, a cacheappropriateness decision engine 246, a poll schedule generator 247, anapplication protocol module 248, a cache or connect selection engine 249having a cache query module 229, and/or a local cache invalidator 244.The cache defeat resolution engine 221 can further include a patternextraction module 222 and/or a cache defeat parameter detector 223. Thecache defeat parameter detector 223 can further include a randomparameter detector 224 and/or a time/date parameter detector 226. Oneembodiment further includes an application cache policy repository 243coupled to the decision engine 246.

In one embodiment, the application behavior detector 236 includes apattern detector 237, a poll interval detector 238, an applicationprofile generator 239, and/or a priority engine 241. The patterndetector 237 can further include a cache defeat parameter detector 223having also, for example, a random parameter detector 233 and/or atime/date parameter detector 234. One embodiment further includes anapplication profile repository 242 coupled to the application profilegenerator 239. The application profile generator 239, and the priorityengine 241 have been described in association with the description ofthe application behavior detector 236 in the example of FIG. 2A.

The cache defeat resolution engine 221 can detect, identify, track,manage, and/or monitor content or content sources (e.g., servers orhosts) which employ identifiers and/or are addressed by identifiers(e.g., resource identifiers such as URLs and/or URIs) with one or moremechanisms that defeat cache or are intended to defeat cache. The cachedefeat resolution engine 221 can, for example, detect from a given datarequest generated by an application or client that the identifierdefeats or potentially defeats cache, where the data request otherwiseaddresses content or responses from a host or server (e.g., applicationserver/content host 110 or 310) that is cacheable.

In one embodiment, the cache defeat resolution engine 221 detects oridentifies cache defeat mechanisms used by content sources (e.g.,application server/content host 110 or 310) using the identifier of adata request detected at the mobile device 250. The cache defeatresolution engine 221 can detect or identify a parameter in theidentifier which can indicate that cache defeat mechanism is used. Forexample, a format, syntax, or pattern of the parameter can be used toidentify cache defeat (e.g., a pattern, format, or syntax as determinedor extracted by the pattern extraction module 222).

The pattern extraction module 222 can parse an identifier into multipleparameters or components and perform a matching algorithm on eachparameter to identify any of which match one or more predeterminedformats (e.g., a date and/or time format, as illustrated in parameters702 shown in FIG. 7). For example, the results of the matching or theparsed out parameters from an identifier can be used (e.g., by the cachedefeat parameter detector 223) to identify cache defeating parameterswhich can include one or more changing parameters.

The cache defeat parameter detector 223, in one embodiment can detectrandom parameters (e.g., by the random parameter detector 224) and/ortime and/or date parameters which are typically used for cache defeat.The cache defeat parameter detector 223 can detect random parameters(e.g., as illustrated in parameters 752 shown in FIG. 7) and/ortime/dates using commonly employed formats for these parameters andperforming pattern matching algorithms and tests.

In addition to detecting patterns, formats, and/or syntaxes, the cachedefeat parameter detector 223 further determines or confirms whether agiven parameter is defeating cache and whether the addressed content canbe cached by the distributed caching system. The cache defeat parameterdetector 223 can detect this by analyzing responses received for theidentifiers utilized by a given data request. In general, a changingparameter in the identifier is identified to indicate cache defeat whenresponses corresponding to multiple data requests are the same even whenthe multiple data requests uses identifiers with the changing parameterbeing different for each of the multiple data requests. For example, therequest/response pairs shown in the examples of FIG. 7 illustrate thatthe responses (704 and 754 in FIG. 7) received are the same, even thoughthe resource identifier includes a parameter (702 and 752 in FIG. 7)that changes with each request.

For example, at least two same responses may be required to identify thechanging parameter as indicating cache defeat. In some instances, atleast three same responses may be required. The requirement for thenumber of same responses needed to determine that a given parameter witha varying value between requests is cache defeating may be applicationspecific, context dependent, and/or user dependent/user specified, or acombination of the above. Such a requirement may also be static ordynamically adjusted by the distributed cache system to meet certainperformance thresholds and/or either explicit/implicit feedbackregarding user experience (e.g., whether the user or application isreceiving relevant/fresh content responsive to requests). More of thesame responses may be required to confirm cache defeat, or for thesystem to treat a given parameter as intended for cache defeat if anapplication begins to malfunction due to response caching and/or if theuser expresses dissatisfaction (explicit user feedback) or the systemdetects user frustration (implicit user cues).

The cache appropriateness decision engine 246 can detect, assess, ordetermine whether content from a content source (e.g., applicationserver/content provider 110 in the example of FIG. 1B) with which amobile device 250 interacts, has content that may be suitable forcaching. In some instances, content from a given applicationserver/content provider (e.g., the server/provider 110 of FIG. 1B) isdetermined to be suitable for caching based on a set of criteria (forexample, criteria specifying time criticality of the content that isbeing requested from the content source). In one embodiment, the localproxy (e.g., the local proxy 175 or 275 of FIG. 1B and FIG. 2A) appliesa selection criteria to store the content from the host server which isrequested by an application as cached elements in a local cache on themobile device to satisfy subsequent requests made by the application.

The selection criteria can also include, by way of example, but notlimitation, state of the mobile device indicating whether the mobiledevice is active or inactive, network conditions, and/or radio coveragestatistics. The cache appropriateness decision engine 246 can any one orany combination of the criteria, and in any order, in identifyingsources for which caching may be suitable.

Once application servers/content providers having identified or detectedcontent that is potentially suitable for local caching on the mobiledevice 250, the cache policy manager 245 can proceed to cache theassociated content received from the identified sources by storingcontent received from the content source as cache elements in a localcache (e.g., local cache 185 or 285 shown in the examples of FIG. 1B andFIG. 2A, respectively) on the mobile device 250. The content source canalso be identified to a proxy server (e.g., proxy server 125 or 325shown in the examples of FIG. 1B and FIG. 3A, respectively) remote fromand in wireless communication with the mobile device 250 such that theproxy server can monitor the content source (e.g., applicationserver/content provider 110) for new or changed data. Similarly, thelocal proxy (e.g., the local proxy 175 or 275 of FIG. 1B and FIG. 2A,respectively) can identify to the proxy server that content receivedfrom a specific application server/content provider is being stored ascached elements in the local cache.

In one embodiment, cache elements are stored in the local cache 285 asbeing associated with a normalized version of an identifier for anidentifier employing one or more parameters intended to defeat cache.The identifier can be normalized by the identifier normalizer module 211and the normalization process can include, by way of example, one ormore of: converting the URI scheme and host to lower-case, capitalizingletters in percent-encoded escape sequences, removing a default port,and removing duplicate slashes.

In another embodiment, the identifier is normalized by removing theparameter for cache defeat and/or replacing the parameter with a staticvalue which can be used to address or be associated with the cachedresponse received responsive to a request utilizing the identifier bythe normalizer 211 or the cache defeat parameter handler 212. Forexample, the cached elements stored in the local cache 285 (shown inFIG. 2A) can be identified using the normalized version of theidentifier or a hash value of the normalized version of the identifier.The hash value of an identifier or of the normalized identifier may begenerated by the hash engine 213.

Once content has been locally cached, the cache policy manager 245 can,upon receiving future polling requests to contact the content server,retrieve the cached elements from the local cache to respond to thepolling request made at the mobile device 250 such that a radio of themobile device is not activated to service the polling request. Suchservicing and fulfilling application (e.g., mobile application) requestslocally via local cache entries allow for more efficient resource andmobile network traffic utilization and management since networkbandwidth and other resources need not be used to request/receive pollresponses which may have not changed from a response that has alreadybeen received at the mobile device 250.

One embodiment of the cache policy manager 245 includes a poll schedulegenerator 247 which can generate a polling schedule for one or moreapplications on the mobile device 250. The polling schedule can specifya polling interval that can be employed by the proxy server (e.g., proxyserver 125 or 325 shown in the examples of FIG. 1B and FIG. 3A) inmonitoring the content source for one or more applications. The pollingschedule can be determined, for example, based on the interval betweenthe polling requests directed to the content source from the mobiledevice. In one embodiment, the poll interval detector 238 of theapplication behavior detector can monitor polling requests directed to acontent source from the mobile device 250 in order to determine aninterval between the polling requests made from any or all application(e.g., mobile application).

In one embodiment, the cache policy manager 245 sends the pollingschedule is sent to the proxy server (e.g., proxy server 125 or 325shown in the examples of FIG. 1B and FIG. 3A) and can be used by theproxy server in monitoring the content source, for example, for changedor new content. The local cache invalidator 244 of the caching policymanager 245 can invalidate cache elements in the local cache (e.g.,cache 185 or 285) when new or changed data is detected from theapplication server/content source for a given request. The new orchanged data can be, for example, detected by the proxy server. When acache entry for a given request/poll has been invalidated and/or removed(e.g., deleted from cache) after invalidation, the use of the radio onthe mobile device 250 can be enabled (e.g., by the local proxy or thecache policy manager 245) to satisfy the subsequent polling requests, asfurther described with reference to the interaction diagram of FIG. 4B.

In another embodiment, the proxy server (e.g., proxy server 125 or 325shown in the examples of FIG. 1B and FIG. 3A) uses a modified version ofa resource identifier used in a data request to monitor a given contentsource (the application server/content host 110 of FIG. 1A and FIG. 1Bto which the data request is addressed) for new or changed data. Forexample, in the instance where the content source or identifier isdetected to employ cache defeat mechanisms, a modified (e.g.,normalized) identifier can be used instead to poll the content source.The modified or normalized version of the identifier can be communicatedto the proxy server by the caching policy manager 245, or morespecifically the cache defeat parameter handler 212 of the identifiernormalizer 211.

The modified identifier used by the proxy server to poll the contentsource on behalf of the mobile device/application (e.g., mobileapplication) may or may not be the same as the normalized identifier.For example, the normalized identifier may be the original identifierwith the changing cache defeating parameter removed whereas the modifiedidentifier uses a substitute parameter in place of the parameter that isused to defeat cache (e.g., the changing parameter replaced with astatic value or other predetermined value known to the local proxyand/or proxy server). The modified parameter can be determined by thelocal proxy 275 and communicated to the proxy server. The modifiedparameter may also be generated by the proxy server (e.g., by theidentifier modifier module 353 shown in the example of FIG. 3C).

One embodiment of the cache policy manager 245 includes a cache orconnect selection engine 249 which can decide whether to use a locallycached entry to satisfy a poll/content request generated at the mobiledevice 250 by an application or widget. For example, the local proxy 275or the cache policy manger 245 can intercept a polling request made byan application (e.g., mobile application) on the mobile device, tocontact the application server/content provider. The selection engine249 can determine whether the content received for the interceptedrequest has been locally stored as cache elements for deciding whetherthe a radio of the mobile device needs to be activated to satisfy therequest made by the application (e.g., mobile application). In oneembodiment, the local proxy 275, in response to determining thatrelevant cached content exists and is still valid, can retrieve thecached elements from the local cache to provide a response to theapplication (e.g., mobile application) which made the polling requestsuch that a radio of the mobile device is not activated to provide theresponse to the application (e.g., mobile application).

In one embodiment, the cached elements stored in the local cache 285(shown in FIG. 2A) can be identified using a normalized version of theidentifier or a hash value of the normalized version of the identifier,for example, using the cache query module 229. Cached elements can bestored with normalized identifiers which have cache defeating parametersremoved or otherwise replaced such that the relevant cached elements canbe identified and retrieved in the future to satisfy other requestsemploying the same type of cache defeat. For example, when an identifierutilized in a subsequent request is determined to be utilizing the samecache defeating parameter, the normalized version of this identifier canbe generated and used to identify a cached response stored in the mobiledevice cache to satisfy the data request. The hash value of anidentifier or of the normalized identifier may be generated by the hashengine 213 of the identifier normalizer 211.

In one embodiment, the local proxy includes a heartbeat manager 267(e.g., as a part of a connection manager shown in the example of FIG.2A). The heart beat manager 267 can include a keep-alive messagedetector 268 and/or an interval tracker 269. In some instances, theheartbeat manager 267 may be coupled to the caching policy manager 245and/or the application behavior detector 236. In some embodiments, theheartbeat manager 267 is partially or wholly internal to one or both ofthe caching policy manager 245 and/or the application behavior detector236.

The heartbeat manager 267 can receive, detect, process, manage analyzeany heartbeat, keep-alive messages or other periodic messages and/orassociated messages, indicators, of the keep-alive messages to indicatehealth or operational status of one or more entities in a network incommunication with the mobile or wireless device on which the localproxy resides.

The heartbeat manager 267 (e.g., or the keep-alive message detector 268)can receive keep-alive messages from content sources or third partyhosts (e.g., application server/content provider 110) with which clientson the mobile device 250 communicates. The heartbeat manager 267 (or thekeep-alive message detector 268) may also receive, detect, identify,extract, or parse keep-alive messages from messages received from aremote proxy server (e.g., proxy server 325). The remote proxy serversends heartbeats or keep-alive messages to indicate functional and/oroperational status to maintain the trust of the mobile device 250 or itslocal proxy 275.

One embodiment of the heartbeat manager 267 further includes an intervaltracker 269 which is able to detect, identify, determine, compute, timeintervals between keep-alive messages sent from the proxy server (e.g.,proxy 325) or any other servers/host.

Using the keep-alive messages received, the time intervals between thekeep-alive messages, and the expectation of future intervals, the localproxy 275 can manage its connections (e.g., via the connection manager265) since it can monitor the health or operational status/functionalstatus of various connections. The interval tracker 269 can track timingintervals of received keep-alive messages or track anticipated orpredicted timing intervals of subsequent keep-alive messages. Forexample, the interval tracker 269 can receive indications about futuretiming of keep-alive messages. Such timing indications can be sent bythe remote proxy (e.g., proxy 325) or any other entities.

Timing indications can be sent to the heartbeat manager 267 (or theinterval tracker 269) such that timing intervals between keep-alives canbe increased to be sent at increasing time intervals, thus decreasingthe number of keep-alives that need to be sent, or in any other fashionwhich conserves network (mobile) network use and/or battery lifeconsumption of the mobile device 250. Sending timing indications offuture keep alives to the heartbeat manager 269 (or interval tracker269), the mobile device 250 or proxy server 225 knows when to expectkeep-alives such that the trust of a remote entity can be maintained orknown.

In general, timing intervals are dynamically adjustable by the sendingparty (e.g., the remote proxy 325) and can be based on real-timecommunication statistics, near real-time communication statistics,historical communication statistics, or any combination thereof. Thetiming can be determined using communication statistics at the mobiledevice 250 or communication statistics at an application server/contentsource (e.g., application server 110).

The rate of polling requests at the mobile device 250 can be determinedby the local proxy 225 (e.g., via the poll interval detector 238 of theapplication behavior detector 236) and can be communicated to the proxyserver (e.g., remote proxy 325) for use in computing timing intervalsbetween keep-alive messages. Rate of content change at an applicationserver (e.g., 110) can be determined by the proxy server 325 and alsoused in determining timing intervals by the proxy server 325, as will befurther described with reference to FIG. 3C.

The timing of keep-alive messages can also be determined based ontime-criticality or time-sensitivity of content provided by the contentsource (e.g., app server/source 110), or criticality of an applicationthat is requesting the content provided by the content source (e.g., bythe prioritization engine 241 of the application behavior detector 236).

Note that the timing indicator can also be communicated to the mobiledevice 250 or local proxy 225 in a manner that conserves mobile networkbandwidth and use. For example, the timing indicator can be batch sentto the mobile device 250 with other messages to make use of when thedevice radio is already on. In one embodiment, the timing iscommunicated to the mobile device with at least some of the keep-alivemessages, a message communicating data (e.g., a response to a mobilerequest), and/or a cache-related message. In general, a cache-relatedmessage can include an updated cache entry for updating a cache entry onthe mobile device 250, and/or an invalidating message indicatingexpiration or irrelevance of the cached entry.

FIG. 3A depicts a block diagram illustrating an example of server-sidecomponents in a distributed proxy and cache system residing on a hostserver 300 that manages traffic in a wireless network for resourceconservation.

The host server 300 generally includes, for example, a network interface308 and/or one or more repositories 312, 314, and 316. Note that server300 may be any portable/mobile or non-portable device, server, clusterof computers and/or other types of processing units (e.g., any number ofa machine shown in the example of FIG. 11) able to receive or transmitsignals to satisfy data requests over a network including any wired orwireless networks (e.g., WiFi, cellular, Bluetooth, etc.).

The network interface 308 can include networking module(s) or devices(s)that enable the server 300 to mediate data in a network with an entitythat is external to the host server 300, through any known and/orconvenient communications protocol supported by the host and theexternal entity. Specifically, the network interface 308 allows theserver 300 to communicate with multiple devices including mobile phonedevices 350 and/or one or more application servers/content providers310.

The host server 300 can store information about connections (e.g.,network characteristics, conditions, types of connections, etc.) withdevices in the connection metadata repository 312. Additionally, anyinformation about third party application or content providers can alsobe stored in the repository 312. The host server 300 can storeinformation about devices (e.g., hardware capability, properties, devicesettings, device language, network capability, manufacturer, devicemodel, OS, OS version, etc.) in the device information repository 314.Additionally, the host server 300 can store information about networkproviders and the various network service areas in the network serviceprovider repository 316.

The communication enabled by network interface 308 allows forsimultaneous connections (e.g., including cellular connections) withdevices 350 and/or connections (e.g., including wired/wireless, HTTP,Internet connections, LAN, WiFi, etc.) with content servers/providers310 to manage the traffic between devices 350 and content providers 310,for optimizing network resource utilization and/or to conserve power(battery) consumption on the serviced devices 350. The host server 300can communicate with mobile devices 350 serviced by different networkservice providers and/or in the same/different network service areas.The host server 300 can operate and is compatible with devices 350 withvarying types or levels of mobile capabilities, including by way ofexample but not limitation, 1G, 2G, 2G transitional (2.5G, 2.75G), 3G(IMT-2000), 3G transitional (3.5G, 3.75G, 3.9G), 4G (IMT-advanced), etc.

In general, the network interface 308 can include one or more of anetwork adaptor card, a wireless network interface card (e.g., SMSinterface, WiFi interface, interfaces for various generations of mobilecommunication standards including but not limited to 1G, 2G, 3G, 3.5G,4G type networks such as LTE, WiMAX, etc.), Bluetooth, WiFi, or anyother network whether or not connected via a router, an access point, awireless router, a switch, a multilayer switch, a protocol converter, agateway, a bridge, a bridge router, a hub, a digital media receiver,and/or a repeater.

The host server 300 can further include server-side components of thedistributed proxy and cache system which can include a proxy server 325and a server cache 335. In one embodiment, the proxy server 325 caninclude an HTTP access engine 345, a caching policy manager 355, a proxycontroller 365, a traffic shaping engine 375, a new data detector 347and/or a connection manager 395.

The HTTP access engine 345 may further include a heartbeat manager 398;the proxy controller 365 may further include a data invalidator module368; the traffic shaping engine 375 may further include a controlprotocol 376 and a batching module 377. Additional or lesscomponents/modules/engines can be included in the proxy server 325 andeach illustrated component.

As used herein, a “module,” a “manager,” a “handler,” a “detector,” an“interface,” a “controller,” a “normalizer,” a “generator,” an“invalidator,” or an “engine” includes a general purpose, dedicated orshared processor and, typically, firmware or software modules that areexecuted by the processor. Depending upon implementation-specific orother considerations, the module, manager, handler, detector, interface,controller, normalizer, generator, invalidator, or engine can becentralized or its functionality distributed. The module, manager,handler, detector, interface, controller, normalizer, generator,invalidator, or engine can include general or special purpose hardware,firmware, or software embodied in a computer-readable (storage) mediumfor execution by the processor. As used herein, a computer-readablemedium or computer-readable storage medium is intended to include allmediums that are statutory (e.g., in the United States, under 35 U.S.C.101), and to specifically exclude all mediums that are non-statutory innature to the extent that the exclusion is necessary for a claim thatincludes the computer-readable (storage) medium to be valid. Knownstatutory computer-readable mediums include hardware (e.g., registers,random access memory (RAM), non-volatile (NV) storage, to name a few),but may or may not be limited to hardware.

In the example of a device (e.g., mobile device 350) making anapplication or content request to an application server or contentprovider 310, the request may be intercepted and routed to the proxyserver 325 which is coupled to the device 350 and the applicationserver/content provider 310. Specifically, the proxy server is able tocommunicate with the local proxy (e.g., proxy 175 and 275 of theexamples of FIG. 1 and FIG. 2 respectively) of the mobile device 350,the local proxy forwards the data request to the proxy server 325 insome instances for further processing and, if needed, for transmissionto the application server/content server 310 for a response to the datarequest.

In such a configuration, the host 300, or the proxy server 325 in thehost server 300 can utilize intelligent information provided by thelocal proxy in adjusting its communication with the device in such amanner that optimizes use of network and device resources. For example,the proxy server 325 can identify characteristics of user activity onthe device 350 to modify its communication frequency. Thecharacteristics of user activity can be determined by, for example, theactivity/behavior awareness module 366 in the proxy controller 365 viainformation collected by the local proxy on the device 350.

In one embodiment, communication frequency can be controlled by theconnection manager 395 of the proxy server 325, for example, to adjustpush frequency of content or updates to the device 350. For instance,push frequency can be decreased by the connection manager 395 whencharacteristics of the user activity indicate that the user is inactive.In one embodiment, when the characteristics of the user activityindicate that the user is subsequently active after a period ofinactivity, the connection manager 395 can adjust the communicationfrequency with the device 350 to send data that was buffered as a resultof decreased communication frequency to the device 350.

In addition, the proxy server 325 includes priority awareness of variousrequests, transactions, sessions, applications, and/or specific events.Such awareness can be determined by the local proxy on the device 350and provided to the proxy server 325. The priority awareness module 367of the proxy server 325 can generally assess the priority (e.g.,including time-criticality, time-sensitivity, etc.) of various events orapplications; additionally, the priority awareness module 367 can trackpriorities determined by local proxies of devices 350.

In one embodiment, through priority awareness, the connection manager395 can further modify communication frequency (e.g., use or radio ascontrolled by the radio controller 396) of the server 300 with thedevices 350. For example, the server 300 can notify the device 350, thusrequesting use of the radio if it is not already in use when data orupdates of an importance/priority level which meets a criteria becomesavailable to be sent.

In one embodiment, the proxy server 325 can detect multiple occurrencesof events (e.g., transactions, content, data received fromserver/provider 310) and allow the events to accumulate for batchtransfer to device 350. Batch transfer can be cumulated and transfer ofevents can be delayed based on priority awareness and/or useractivity/application behavior awareness as tracked by modules 367 and/or366. For example, batch transfer of multiple events (of a lowerpriority) to the device 350 can be initiated by the batching module 377when an event of a higher priority (meeting a threshold or criteria) isdetected at the server 300. In addition, batch transfer from the server300 can be triggered when the server receives data from the device 350,indicating that the device radio is already in use and is thus on. Inone embodiment, the proxy server 325 can order the each messages/packetsin a batch for transmission based on event/transaction priority suchthat higher priority content can be sent first in case connection islost or the battery dies, etc.

In one embodiment, the server 300 caches data (e.g., as managed by thecaching policy manager 355) such that communication frequency over anetwork (e.g., cellular network) with the device 350 can be modified(e.g., decreased). The data can be cached, for example, in the servercache 335 for subsequent retrieval or batch sending to the device 350 topotentially decrease the need to turn on the device 350 radio. Theserver cache 335 can be partially or wholly internal to the host server300, although in the example of FIG. 3A it is shown as being external tothe host 300. In some instances, the server cache 335 may be the same asand/or integrated in part or in whole with another cache managed byanother entity (e.g., the optional caching proxy server 199 shown in theexample of FIG. 1B), such as being managed by an applicationserver/content provider 310, a network service provider, or anotherthird party.

In one embodiment, content caching is performed locally on the device350 with the assistance of host server 300. For example, proxy server325 in the host server 300 can query the application server/provider 310with requests and monitor changes in responses. When changed or newresponses are detected (e.g., by the new data detector 347), the proxyserver 325 can notify the mobile device 350 such that the local proxy onthe device 350 can make the decision to invalidate (e.g., indicated asout-dated) the relevant cache entries stored as any responses in itslocal cache. Alternatively, the data invalidator module 368 canautomatically instruct the local proxy of the device 350 to invalidatecertain cached data, based on received responses from the applicationserver/provider 310. The cached data is marked as invalid, and can getreplaced or deleted when new content is received from the content server310.

Note that data change can be detected by the detector 347 in one or moreways. For example, the server/provider 310 can notify the host server300 upon a change. The change can also be detected at the host server300 in response to a direct poll of the source server/provider 310. Insome instances, the proxy server 325 can in addition, pre-load the localcache on the device 350 with the new/updated data. This can be performedwhen the host server 300 detects that the radio on the mobile device isalready in use, or when the server 300 has additional content/data to besent to the device 350.

One or more the above mechanisms can be implemented simultaneously oradjusted/configured based on application (e.g., different policies fordifferent servers/providers 310). In some instances, the sourceprovider/server 310 may notify the host 300 for certain types of events(e.g., events meeting a priority threshold level). In addition, theprovider/server 310 may be configured to notify the host 300 at specifictime intervals, regardless of event priority.

In one embodiment, the proxy server 325 of the host 300 canmonitor/track responses received for the data request from the contentsource for changed results prior to returning the result to the mobiledevice, such monitoring may be suitable when data request to the contentsource has yielded same results to be returned to the mobile device,thus preventing network/power consumption from being used when no newchanges are made to a particular requested. The local proxy of thedevice 350 can instruct the proxy server 325 to perform such monitoringor the proxy server 325 can automatically initiate such a process uponreceiving a certain number of the same responses (e.g., or a number ofthe same responses in a period of time) for a particular request.

In one embodiment, the server 300, through the activity/behaviorawareness module 366, is able to identify or detect user activity at adevice that is separate from the mobile device 350. For example, themodule 366 may detect that a user's message inbox (e.g., email or typesof inbox) is being accessed. This can indicate that the user isinteracting with his/her application using a device other than themobile device 350 and may not need frequent updates, if at all.

The server 300, in this instance, can thus decrease the frequency withwhich new or updated content is sent to the mobile device 350, oreliminate all communication for as long as the user is detected to beusing another device for access. Such frequency decrease may beapplication specific (e.g., for the application with which the user isinteracting with on another device), or it may be a general frequencydecrease (E.g., since the user is detected to be interacting with oneserver or one application via another device, he/she could also use itto access other services.) to the mobile device 350.

In one embodiment, the host server 300 is able to poll content sources310 on behalf of devices 350 to conserve power or battery consumption ondevices 350. For example, certain applications on the mobile device 350can poll its respective server 310 in a predictable recurring fashion.Such recurrence or other types of application behaviors can be trackedby the activity/behavior module 366 in the proxy controller 365. Thehost server 300 can thus poll content sources 310 for applications onthe mobile device 350 that would otherwise be performed by the device350 through a wireless (e.g., including cellular connectivity). The hostserver can poll the sources 310 for new or changed data by way of theHTTP access engine 345 to establish HTTP connection or by way of radiocontroller 396 to connect to the source 310 over the cellular network.When new or changed data is detected, the new data detector 347 cannotify the device 350 that such data is available and/or provide thenew/changed data to the device 350.

In one embodiment, the connection manager 395 determines that the mobiledevice 350 is unavailable (e.g., the radio is turned off) and utilizesSMS to transmit content to the device 350, for instance, via the SMSCshown in the example of FIG. 1B. SMS is used to transmit invalidationmessages, batches of invalidation messages, or even content in the casewhere the content is small enough to fit into just a few (usually one ortwo) SMS messages. This avoids the need to access the radio channel tosend overhead information. The host server 300 can use SMS for certaintransactions or responses having a priority level above a threshold orotherwise meeting a criteria. The server 300 can also utilize SMS as anout-of-band trigger to maintain or wake-up an IP connection as analternative to maintaining an always-on IP connection.

In one embodiment, the connection manager 395 in the proxy server 325(e.g., the heartbeat manager 398) can generate and/or transmit heartbeatmessages on behalf of connected devices 350 to maintain a backendconnection with a provider 310 for applications running on devices 350.The heartbeat manager 398 can also send periodic messages or keep-alivemessages to a mobile device (e.g., mobile device 250). Such keep-alivemessages can be used to signal health or operational status of the proxyserver 325 to the mobile device 250 and/or its local proxy 225. Thefunctions and features of the heartbeat manager 398 are furtherillustrated in the example of FIG. 3C.

For example, in the distributed proxy system, local cache on the device350 can prevent any or all heartbeat messages needed to maintain TCP/IPconnections required for applications from being sent over the cellular,or other, network and instead rely on the proxy server 325 on the hostserver 300 to generate and/or send the heartbeat messages to maintain aconnection with the backend (e.g., application server/provider 110 inthe example of FIG. 1A). The proxy server 325 (or the heartbeat manager398) can generate the keep-alive (heartbeat) messages independent of theoperations of the local proxy on the mobile device.

The repositories 312, 314, and/or 316 can additionally store software,descriptive data, images, system information, drivers, and/or any otherdata item utilized by other components of the host server 300 and/or anyother servers for operation. The repositories may be managed by adatabase management system (DBMS), for example, which may be but is notlimited to Oracle, DB2, Microsoft Access, Microsoft SQL Server,PostgreSQL, MySQL, FileMaker, etc.

The repositories can be implemented via object-oriented technologyand/or via text files and can be managed by a distributed databasemanagement system, an object-oriented database management system(OODBMS) (e.g., ConceptBase, FastDB Main Memory Database ManagementSystem, JDOlnstruments, ObjectDB, etc.), an object-relational databasemanagement system (ORDBMS) (e.g., Informix, OpenLink Virtuoso, VMDS,etc.), a file system, and/or any other convenient or known databasemanagement package.

FIG. 3B depicts a block diagram illustrating a further example ofcomponents in the caching policy manager 355 in the cache system shownin the example of FIG. 3A which is capable of caching and adaptingcaching strategies for application (e.g., mobile application) behaviorand/or network conditions.

The caching policy manager 355, in one embodiment, can further include ametadata generator 303, a cache look-up engine 305, an applicationprotocol module 356, a content source monitoring engine 357 having apoll schedule manager 358, a response analyzer 361, and/or an updated ornew content detector 359. In one embodiment, the poll schedule manager358 further includes a host timing simulator 358 a, a long poll requestdetector/manager 358 b, a schedule update engine 358 c, and/or a timeadjustment engine 358 d. The metadata generator 303 and/or the cachelook-up engine 305 can be coupled to the cache 335 (or, server cache)for modification or addition to cache entries or querying thereof.

In one embodiment, the proxy server (e.g., the proxy server 125 or 325of the examples of FIG. 1B and FIG. 3A) can monitor a content source fornew or changed data via the monitoring engine 357. The proxy server, asshown, is an entity external to the mobile device 250 of FIG. 2A-B. Thecontent source (e.g., application server/content provider 110 of FIG.1B) can be one that has been identified to the proxy server (e.g., bythe local proxy) as having content that is being locally cached on amobile device (e.g., mobile device 150 or 250). The content source canbe monitored, for example, by the monitoring engine 357 at a frequencythat is based on polling frequency of the content source at the mobiledevice. The poll schedule can be generated, for example, by the localproxy and sent to the proxy server. The poll frequency can be trackedand/or managed by the poll schedule manager 358.

For example, the proxy server can poll the host (e.g., contentprovider/application server) on behalf of the mobile device and simulatethe polling behavior of the client to the host via the host timingsimulator 358 a. The polling behavior can be simulated to includecharacteristics of a long poll request-response sequences experienced ina persistent connection with the host (e.g., by the long poll requestdetector/manager 358 b). Note that once a polling interval/behavior isset, the local proxy 275 on the device-side and/or the proxy server 325on the server-side can verify whether application and applicationserver/content host behavior match or can be represented by thispredicted pattern. In general, the local proxy and/or the proxy servercan detect deviations and, when appropriate, re-evaluate and compute,determine, or estimate another polling interval.

In one embodiment, the caching policy manager 355 on the server-side ofthe distribute proxy can, in conjunction with or independent of theproxy server 275 on the mobile device, identify or detect long pollrequests. For example, the caching policy manager 355 can determine athreshold value to be used in comparison with a response delay intervaltime (interval time ‘D’ shown in the example timing diagram of FIG.17A-B) in a request-response sequence for an application request toidentify or detect long poll requests, possible long poll requests(e.g., requests for a persistent connection with a host with which theclient communicates including, but not limited to, a long-held HTTPrequest, a persistent connection enabling COMET style push, request forHTTP streaming, etc.), or other requests which can otherwise be treatedas a long poll request.

For example, the threshold value can be determined by the proxy 325using response delay interval times for requests generated byclients/applications across mobile devices which may be serviced bymultiple different cellular or wireless networks. Since the proxy 325resides on host 300 is able to communicate with multiple mobile devicesvia multiple networks, the caching policy manager 355 has access toapplication/client information at a global level which can be used insetting threshold values to categorize and detect long polls.

By tracking response delay interval times across applications acrossdevices over different or same networks, the caching policy manager 355can set one or more threshold values to be used in comparison withresponse delay interval times for long poll detection. Threshold valuesset by the proxy server 325 can be static or dynamic, and can beassociated with conditions and/or a time-to-live (an expirationtime/date in relative or absolute terms).

In addition, the caching policy manager 355 of the proxy 325 can furtherdetermine the threshold value, in whole or in part, based on networkdelays of a given wireless network, networks serviced by a given carrier(service provider), or multiple wireless networks. The proxy 325 canalso determine the threshold value for identification of long pollrequests based on delays of one or more application server/contentprovider (e.g., 110) to which application (e.g., mobile application) ormobile client requests are directed.

The proxy server can detect new or changed data at a monitored contentsource and transmits a message to the mobile device notifying it of sucha change such that the mobile device (or the local proxy on the mobiledevice) can take appropriate action (e.g., to invalidate the cacheelements in the local cache). In some instances, the proxy server (e.g.,the caching policy manager 355) upon detecting new or changed data canalso store the new or changed data in its cache (e.g., the server cache135 or 335 of the examples of FIG. 1B and FIG. 3A, respectively). Thenew/updated data stored in the server cache 335 can be used in someinstances to satisfy content requests at the mobile device; for example,it can be used after the proxy server has notified the mobile device ofthe new/changed content and that the locally cached content has beeninvalidated.

The metadata generator 303, similar to the metadata generator 203 shownin the example of FIG. 2B, can generate metadata for responses cachedfor requests at the mobile device 250. The metadata generator 303 cangenerate metadata for cache entries stored in the server cache 335.Similarly, the cache look-up engine 305 can include the same or similarfunctions are those described for the cache look-up engine 205 shown inthe example of FIG. 2B.

The response analyzer 361 can perform any or all of the functionalitiesrelated to analyzing responses received for requests generated at themobile device 250 in the same or similar fashion to the responseanalyzer 246 d of the local proxy shown in the example of FIG. 2B. Sincethe proxy server 325 is able to receive responses from the applicationserver/content source 310 directed to the mobile device 250, the proxyserver 325 (e.g., the response analyzer 361) can perform similarresponse analysis steps to determine cacheability, as described for theresponse analyzer of the local proxy. Examples of response analysisprocedures are also described in conjunction with the flow charts shownin the examples of FIG. 11-13. The responses can be analyzed in additionto or in lieu of the analysis that can be performed at the local proxy275 on the mobile device 250.

Furthermore, the schedule update engine 358 c can update the pollinginterval of a given application server/content host based on applicationrequest interval changes of the application at the mobile device 250 asdescribed for the schedule update engine in the local proxy 275. Thetime adjustment engine 358 d can set an initial time at which polls ofthe application server/content host is to begin to prevent the servingof out of date content once again before serving fresh content asdescribed for the schedule update engine in the local proxy 275. Boththe schedule updating and the time adjustment algorithms can beperformed in conjunction with or in lieu of the similar processesperformed at the local proxy 275 on the mobile device 250.

FIG. 3C depicts a block diagram illustrating another example ofcomponents in the caching policy manager 355 in the proxy server 375 onthe server-side of the distributed proxy system shown in the example ofFIG. 3A which is capable of managing and detecting cache defeatingmechanisms and monitoring content sources, and can further include or becoupled to components (e.g., heartbeat manager 398) for managing thetiming and/or generation of keep-alive messages.

The caching policy manager 355, in one embodiment, can further include acache defeating source manager 352, a content source monitoring engine357 having a poll schedule manager 358, and/or an updated or new contentdetector 359. The cache defeating source manager 352 can further includean identifier modifier module 353 and/or an identifier pattern trackingmodule 354.

In one embodiment, the proxy server (e.g., the proxy server 125 or 325of the examples of FIG. 1B and FIG. 3A) can monitor a content source fornew or changed data via the monitoring engine 357. The content source(e.g., application server/content provider 110 of FIG. 1B or 310 of FIG.3A) can be one that has been identified to the proxy server (e.g., bythe local proxy) as having content that is being locally cached on amobile device (e.g., mobile device 150 or 250). The content source 310can be monitored, for example, by the monitoring engine 357 at afrequency that is based on polling frequency of the content source atthe mobile device. The poll schedule can be generated, for example, bythe local proxy and sent to the proxy server 325. The poll frequency canbe tracked and/or managed by the poll schedule manager 358.

In one embodiment, the proxy server 325 uses a normalized identifier ormodified identifier in polling the content source 310 to detect new orchanged data (responses). The normalized identifier or modifiedidentifier can also be used by the proxy server 325 in storing responseson the server cache 335. In general, the normalized or modifiedidentifiers can be used when cache defeat mechanisms are employed forcacheable content. Cache defeat mechanisms can be in the form of achanging parameter in an identifier such as a URI or URL and can includea changing time/data parameter, a randomly varying parameter, or othertypes parameters.

The normalized identifier or modified identifier removes or otherwisereplaces the changing parameter for association with subsequent requestsand identification of associated responses and can also be used to pollthe content source. In one embodiment, the modified identifier isgenerated by the cache defeating source manager 352 (e.g., theidentifier modifier module 353) of the caching policy manager 355 on theproxy server 325 (server-side component of the distributed proxysystem). The modified identifier can utilize a substitute parameter(which is generally static over a period of time) in place of thechanging parameter that is used to defeat cache.

The cache defeating source manager 352 optionally includes theidentifier pattern tracking module 354 to track, store, and monitor thevarious modifications of an identifier or identifiers that addresscontent for one or more content sources (e.g., applicationserver/content host 110 or 310) to continuously verify that the modifiedidentifiers and/or normalized identifiers used by the proxy server 325to poll the content sources work as predicted or intended (e.g., receivethe same responses or responses that are otherwise still relevantcompared to the original, unmodified identifier).

In the event that the pattern tracking module 354 detects a modificationor normalization of an identifier that causes erratic or unpredictablebehavior (e.g., unexpected responses to be sent) on the content source,the tracking module 354 can log the modification and instruct the cachedefeating source manager 352 to generate anothermodification/normalization, or notify the local proxy (e.g., local proxy275) to generate another modification/normalization for use in pollingthe content source. In the alternative or in parallel, the requests fromthe given mobile application/client on the mobile device (e.g., mobiledevice 250) can temporarily be sent across the network to the contentsource for direct responses to be provided to the mobile device and/oruntil a modification of an identifier which works can be generated.

In one embodiment, responses are stored as server cache elements in theserver cache when new or changed data is detected for a response that isalready stored on a local cache (e.g., cache 285) of the mobile device(e.g., mobile device 250). Therefore, the mobile device or local proxy275 can connect to the proxy server 325 to retrieve the new or changeddata for a response to a request which was previously cached locally inthe local cache 285 (now invalid, out-dated, or otherwise determined tobe irrelevant).

The proxy server 325 can detect new or changed data at a monitoredapplication server/content host 310 and transmits a message to themobile device notifying it of such a change such that the mobile device(or the local proxy on the mobile device) can take appropriate action(e.g., to invalidate the cache elements in the local cache). In someinstances, the proxy server (e.g., the caching policy manager 355), upondetecting new or changed data, can also store the new or changed data inits cache (e.g., the server cache 135 or 335 of the examples of FIG. 1Band FIG. 3A, respectively). The updated/new data stored in the servercache can be used, in some instances, to satisfy content requests at themobile device; for example, it can be used after the proxy server hasnotified the mobile device of the new/changed content and that thelocally cached content has been invalidated.

One embodiment of the proxy server 325 includes a heartbeat manager 398(e.g., as a component of the connection manager 395 shown in FIG. 3A).The heartbeat manager 398 can further include one or more of, akeep-alive message generator 321, an interval setting/adjusting agent322, a keep-alive message sender 323, and/or a timing indication engine324.

The heartbeat manager 398 manages the need for heartbeats or keep-alivemessages and associated timing to a mobile device (e.g., mobile device250) to indicate functional or operational status such that the mobiledevice can maintain trust in the proxy server 325. The proxy 325 cangenerate the keep-alive messages (e.g., keep-alive message generator321) and send the keep-alive messages (e.g., via the keep-alive messagegenerator 323) when needed or when appropriate.

In general, the proxy server 325 detects the need to begin to usekeep-alive messages when data communication rates with the mobile devicedecreases. In one embodiment, the proxy server 325 (or keep-alivemessage sender 323) sends keep-alive messages or other periodic messagesto indicate operational state to the mobile device in response to adecrease in the rates of data communications with the mobile device orafter communication with the mobile device 250 has been dormant for atime period. The decrease or change in rate of data communication withthe mobile device 250 can be determined through monitoring by the proxyserver 325 (e.g., the activity or behavior awareness module 366 shown inFIG. 3A).

In one embodiment, the sender 323 sends keep-alive messages orsubsequent messages which indicate operational or state of health statusto the mobile device 250 at increasing time intervals such that thenumber of periodic messages sent over the wireless network can bedecreased to conserve network and device resources consumed bykeep-alive signaling. The interval setting/adjusting agent 322 canincrease the intervals in any known or convenient fashion. In oneembodiment, the interval setting/adjusting agent 322 increases theintervals between the subsequent periodic messages in a multiplicativefashion.

In one embodiment the interval setting/adjusting agent 322 can set,adjust, determine, and/or compute the timing interval between any twokeep-alive messages for a given mobile client or any mobile device.Since the proxy server 325 can operate with multiple clients (e.g.,multiple mobile applications) and/or multiple mobile devices, theinterval setting/adjusting agent 322 can manage, track or compute thetiming intervals for signaling of health status to different entities.

In one embodiment, the proxy server 325 detects the rate of contentchange at a source (e.g., via the content source monitoring engine 357of the caching policy manager 355). The timing between keep-alivemessages or other periodic messages to indicate operational/functionalstatus can be adjusted/set/configured based in part or in whole on therate of content change at the source (e.g., application server/contentsource). For example, the time interval between the keep-alive messagescan be set to be proportional to the rate of the content change at thecontent source. The timing between keep-alive messages can also bedetermined in part of in whole based on time-criticality ortime-sensitivity of content provided by the content source, orcriticality of an application that is requesting the content provided bythe content source (e.g., app server 110). The time-criticality andsensitivity can be determined by the proxy server 325 (e.g., via thepriority awareness module 367) and/or by the local proxy (e.g., 225) ofthe mobile device 250.

In addition, timing indicators (e.g., interval or interval indicator)can be sent to indicate to the mobile client or mobile device 250 whensubsequent keep-alive messages will be sent (e.g., a timing parameterindicating timing intervals between keep-alive messages), by the timingindication engine 324. The timing indication engine 324 can generallyacknowledge to the mobile device that the subsequent periodic messageswill be sent at increased intervals. The timing indicators can be sentwith (e.g., batched with) other messages that need to be sent to a givenmobile device to utilize an existing in-use network channel and toprevent the mobile device from powering on an otherwise dormant radio.Various ways and channels to batch the transmission of timing indicatorsare further illustrated in the example of FIG. 27.

For example, timing indicators can also be sent with one or more of theperiodic keep-alive messages to conserve bandwidth utilization. Timingindicators can also be sent with one or more cache-related messages sentto the mobile device 250 regarding one or more cache entries stored inthe local cache (e.g., cache 285 of the mobile device 250) such as acache-update or cache-invalidate message.

In some instances, keep-alive messages need to be sent to the mobiledevice 250 when the radio is dormant or otherwise inactive orinaccessible. The proxy server 325 (e.g., keep-alive message sender 323)can then instead send the keep-alive messages over SMS or over ansignaling or control channel so as to not require a power-on of themobile device radio.

FIG. 4 depicts a diagram showing how data requests from a mobile device450 to an application server/content provider 495 in a wireless networkcan be coordinated by a distributed proxy system 460 in a manner suchthat network and battery resources are conserved through using contentcaching and monitoring performed by the distributed proxy system 460.

In satisfying application or client requests on a mobile device 450without the distributed proxy system 460, the mobile device 450, or thesoftware widget executing on the device 450, performs a data request 402(e.g., an HTTP GET, POST, or other request) directly to the applicationserver 495 and receives a response 404 directly from the server/provider495. If the data has been updated, the widget 455 on the mobile device450 can refreshes itself to reflect the update and waits for smallperiod of time and initiates another data request to the server/provider495.

In one embodiment, the requesting client or software widget 455 on thedevice 450 can utilize the distributed proxy system 460 in handling thedata request made to server/provider 495. In general, the distributedproxy system 460 can include a local proxy 465 (which is typicallyconsidered a client-side component of the system 460 and can reside onthe mobile device 450), a caching proxy 475 (considered a server-sidecomponent 470 of the system 460 and can reside on the host server 485 orbe wholly or partially external to the host server 485), and a hostserver 485. The local proxy 465 can be connected to the caching proxy475 and host server 485 via any network or combination of networks.

When the distributed proxy system 460 is used for data/applicationrequests, the widget 455 can perform the data request 406 via the localproxy 465. The local proxy 465, can intercept the requests made bydevice applications, and can identify the connection type of the request(e.g., an HTTP get request or other types of requests). The local proxy465 can then query the local cache for any previous information aboutthe request (e.g., to determine whether a locally stored response isavailable and/or still valid). If a locally stored response is notavailable or if there is an invalid response stored, the local proxy 465can update or store information about the request, the time it was made,and any additional data, in the local cache. The information can beupdated for use in potentially satisfying subsequent requests.

The local proxy 465 can then send the request to the host server 485 andthe host server 485 can perform the request 406 and returns the resultsin response 408. The local proxy 465 can store the result and, inaddition, information about the result and returns the result to therequesting widget 455.

In one embodiment, if the same request has occurred multiple times(within a certain time period) and it has often yielded same results,the local proxy 465 can notify 410 the server 485 that the requestshould be monitored (e.g., steps 412 and 414) for result changes priorto returning a result to the local proxy 465 or requesting widget 455.

In one embodiment, if a request is marked for monitoring, the localproxy 465 can now store the results into the local cache. Now, when thedata request 416, for which a locally response is available, is made bythe widget 455 and intercepted at the local proxy 465, the local proxy465 can return the response 418 from the local cache without needing toestablish a connection communication over the wireless network.

In addition, the server proxy performs the requests marked formonitoring 420 to determine whether the response 422 for the givenrequest has changed. In general, the host server 485 can perform thismonitoring independently of the widget 455 or local proxy 465operations. Whenever an unexpected response 422 is received for arequest, the server 485 can notify the local proxy 465 that the responsehas changed (e.g., the invalidate notification in step 424) and that thelocally stored response on the client should be erased or replaced witha new response.

In this case, a subsequent data request 426 by the widget 455 from thedevice 450 results in the data being returned from host server 485(e.g., via the caching proxy 475), and in step 428, the request issatisfied from the caching proxy 475. Thus, through utilizing thedistributed proxy system 460, the wireless (cellular) network isintelligently used when the content/data for the widget or softwareapplication 455 on the mobile device 450 has actually changed. As such,the traffic needed to check for the changes to application data is notperformed over the wireless (cellular) network. This reduces the amountof generated network traffic and shortens the total time and the numberof times the radio module is powered up on the mobile device 450, thusreducing battery consumption and, in addition, frees up networkbandwidth.

FIG. 5 depicts a diagram showing one example process for implementing ahybrid IP and SMS power saving mode on a mobile device 550 using adistributed proxy and cache system (e.g., such as the distributed systemshown in the example of FIG. 1B).

In step 502, the local proxy (e.g., proxy 175 in the example of FIG. 1B)monitors the device for user activity. When the user is determined to beactive, server push is active. In this way, always-on-push IP connectioncan be maintained and, if available, SMS triggers can be immediatelysent to the mobile device 550 as it becomes available.

In process 504, after the user has been detected to be inactive or idleover a period of time (e.g., the example is shown for a period ofinactivity of 20 minutes), the local proxy can adjust the device to gointo the power saving mode. In the power saving mode, when the localproxy receives a message or a correspondence from a remote proxy (e.g.,the server proxy 135 in the example of FIG. 1B) on the server-side ofthe distributed proxy and cache system, the local proxy can respond witha call indicating that the device 550 is currently in power save mode(e.g., via a power save remote procedure call). In some instances, thelocal proxy can take the opportunity to notify multiple accounts orproviders (e.g., 510A, and 510B) of the current power save status (e.g.,timed to use the same radio power-on event).

In one embodiment, the response from the local proxy can include a time(e.g., the power save period) indicating to the remote proxy (e.g.,server proxy 135) and/or the application server/providers 510A/B whenthe device 550 is next able to receive changes or additional data. Adefault power savings period can be set by the local proxy.

In one embodiment, if new, changed, or different data or event isreceived before the end of any one power saving period, then the waitperiod communicated to the servers 510A/B can be the existing period,rather than an incremented time period. In response, the remote proxyserver, upon receipt of power save notification from the device 550, canstop sending changes (data or SMSS) for the period of time requested(the wait period). At the end of the wait period, any notificationsreceived can be acted upon; for example, changes sent to the device 550as a single batched event or as individual events. If no notificationscome in, then push can be resumed with the data or an SMS being sent tothe device 550. The proxy server can time the poll or data collect eventto optimize batch sending content to the mobile device 550 to increasethe chance that the client will receive data at the next radio power onevent.

Note that the wait period can be updated in operation in real time toaccommodate operating conditions. For example, the local proxy canadjust the wait period on the fly to accommodate the different delaysthat occur in the system.

Detection of user activity in step 508 at the device 550 causes thepower save mode to be exited. When the device 550 exits power save mode,it can begin to receive any changes associated with any pendingnotifications. If a power saving period has expired, then no power savecancel call may be needed as the proxy server will already be intraditional push operation mode.

In one embodiment, power save mode is not applied when the device 550 isplugged into a charger. This setting can be reconfigured or adjusted bythe user or another party. In general, the power save mode can be turnedon and off, for example, by the user via a user interface on device 550.In general, timing of power events to receive data can be synchronizedwith any power save calls to optimize radio use.

FIG. 6 depicts another flow diagram illustrating an example process fordistributed content caching between a mobile device and a proxy serverand the distributed management of content caching.

As shown in the distributed system interaction diagram in the example ofFIG. 4, the disclosed technology is a distributed caching model withvarious aspects of caching tasks split between the client-side/mobiledevice side (e.g., mobile device 450 in the example of FIG. 4) and theserver side (e.g., server side 470 including the host server 485 and/orthe optional caching proxy 475).

In general the device-side responsibilities can include deciding whethera response to a particular request can be and/or should be cached. Thedevice-side of the proxy can make this decision based on information(e.g., timing characteristics, detected pattern, detected pattern withheuristics, indication of predictability or repeatability) collectedfrom/during both request and response and cache it (e.g., storing it ina local cache on the mobile device). The device side can also notify theserver-side in the distributed cache system of the local cache event andnotify it monitor the content source (e.g., application server/contentprovider 110 of FIG. 1A-B).

The device side can further instruct the server side of the distributedproxy to periodically validate the cache response (e.g., by way ofpolling, or sending polling requests to the content source). The deviceside can further decide whether a response to a particular cache requestshould be returned from the local cache (e.g., whether a cache hit isdetected). The decision can be made by the device side (e.g., the localproxy on the device) using information collected from/during requestand/or responses received from the content source.

In general, the server-side responsibilities can include validatingcached responses for relevancy (e.g., determine whether a cachedresponse is still valid or relevant to its associated request). Theserver-side can send the mobile device an invalidation request to notifythe device side when a cached response is detected to be no longer validor no longer relevant (e.g., the server invalidates a given contentsource). The device side then can remove the response from the localcache.

The diagram of FIG. 6 illustrates caching logic processes performed foreach detected or intercepted request (e.g., HTTP request) detected at amobile device (e.g., client-side of the distributed proxy). In step 602,the client-side of the proxy (e.g., local proxy 275 shown in FIG. 2A-Bor mobile device 450 of FIG. 4) receives a request (from an application(e.g., mobile application) or mobile client). In step 604, URL isnormalized and in step 606 the client-side checks to determine if therequest is cacheable. If the request is determined to be not cacheablein step 612, the request is sent to the source (applicationserver/content provider) in step 608 and the response is received 610and delivered to the requesting application 622, similar to arequest-response sequence without interception by the client side proxy.

If the request is determined to be cacheable, in step 612, theclient-side looks up the cache to determine whether a cache entry existsfor the current request. If so, in step 624, the client-side candetermine whether the entry is valid and if so, the client side cancheck the request to see if includes a validator (e.g., a modifiedheader or an entity tag) in step 628. For example, the concept ofvalidation is eluded to in section 13.3 of RFC 2616 which describes inpossible types of headers (e.g., eTAG, Modified_Since, must_revlaidate,pragma no_cache) and forms a validating response 632 if so to bedelivered to the requesting application in step 622. If the request doesnot include a validator as determined by step 628, a response is formedfrom the local cache in step 630 and delivered to the requestingapplication in step 622. This validation step can be used for contentthat would otherwise normally be considered un-cacheable.

If, instead, in step 624, the cache entry is found but determined to beno longer valid or invalid, the client side of the proxy sends therequest 616 to the content source (application server/content host) andreceives a response directly from the source in step 618. Similarly, ifin step 612, a cache entry was not found during the look up, the requestis also sent in step 616. Once the response is received, the client sidechecks the response to determine if it is cacheable in step 626. If so,the response is cached in step 620. The client then sends another pollin step 614 and then delivers the response to the requesting applicationin step 622.

FIG. 7 depicts an interaction diagram showing cache management by adistributed proxy system 760 of content delivered to an application(e.g., mobile application) 755 over a long-held request while ensuringfreshness of content delivered. The optional incorporation of keep-alivemessage management and timing with cache management for long-held typeHTTP requests are also illustrated.

The diagram illustrates an example process for how cached responsesreceived in long-held requests (e.g., long-held HTTP request, longpolls, or HTTP streaming) are provided to the requesting application 755and management of expired/invalid/non-relevant cache entries. Along-held request can be any request for a persistent connection that isheld between the device and the server until a response is available atthe server to be sent (or pushed) to the device. The long-held requestor long-held HTTP request can allow the device/server interaction tosimulate content push over the persistent connection (e.g., COMET stylepush), for example, over a persisted connection over HTTP.

In step 702, the application 755 sends a request which is detected andintercepted by the local proxy 765 on the mobile device 750 on theclient/device-side of the proxy system 760. Note that therequest-response sequence 702, 704, 706, and 708 shown occurs after along poll hunting period which may sometimes be performed by theapplication (e.g., mobile application) sending long poll requests. Thelong poll hunting period may or may not be performed, but whenperformed, it allows the requesting application 755 to find the longestamount of time it can hold a request with the end server/provider 795open before the connection times out (e.g., due to network reason, suchas socket closures).

A timing diagram showing characteristics request-response timingsequences is further illustrated in the example of FIG. 8. In general,the device proxy 750 or local proxy 765 is able to detectrequest-response pattern sequences initiated from the application 755while long poll hunting and can wait until the hunting period hassettled prior to caching responses from long poll request. Therequest-response steps shown between 702 and 710 occur after any longpoll hunting request/response pairs if it was performed by therequesting application 755.

The request is sent to the server/provider 795 in step 704 and therequest times out or closes in 706 when the server 795 sends a responsein step 708 back to the application 755 on the device side 750. Theconnection times out when the server 795 sends a response in step 708due to the nature of the long-held request send in step 702. Theresponse when sent is also intercepted by the local proxy 765 on themobile side 750 of the distributed proxy 760 for local caching.

Once cached, the local proxy 765 notifies the server-side 770 of theproxy of the system 760 and requests that the server-side 770 proxy(e.g., the host server 785) begin to monitor the server/provider 795 instep 712. In step 714, the server-side proxy 770 now begins to sendrequests to the server/provider in order to monitor responses received716 from the server/provider 795.

The next time the application 755 sends the request 718, the local proxy765 determines that a local cache entry now exists and waits for aperiod of time 720 (e.g., a long poll interval) before providing thecached response back to the application 755 in step 722. The local proxy765 allows the period of time to elapse to simulate the actual behaviorof the server/provider 795 with the application 755. Since in an actuallong poll request which goes over the network, a response is notreceived until after some delay, characteristic of the given long poll.

Starting at step 724, another request is sent from the application(e.g., mobile application) 755 when the response from theserver/provider 795 in step 726 is validated. The local proxy 765 waitsfor an interval in step 728 before replying with the cache entry in step744. However, in the interim, the server-side proxy 770 in monitoringresponses sends a request in step 730 to the server/provider 795 anddetects content change in the response received 732 from theserver/provider 795 in step 734. The server-side 770 proxy thus cachesthe changed/updated response data at the server-side proxy in step 736and notifies the local proxy 765 to invalidate the associated cacheentry 738. Note that in conjunction with the invalidation message 738,the proxy 775 or host server 785 can also send keep-alive relatedmessages 701 (e.g., timing interval or other forms of intervalindicators).

The local proxy 765, in response to receiving an invalidation notice,sets the associated entry to be invalidated as being ‘transient’ in step740, or otherwise annotated or indicated to be marked for deletion orremoval. At this point, the local proxy 765 replies to the application755 again with the transient cache in step 744. The local proxy 765 alsoconnects to the server-side proxy 770 to obtain the new cached data atthe server-side 770 in step 742 and receives a response (the new/updatedresponse) at step 746. Note that in conjunction with the sending of theresponse message in 746, the proxy 775 or host server 785 can also sendkeep-alive related messages 701 (e.g., timing interval or other forms ofinterval indicators) to the mobile device 750 (e.g., the keep aliverelated message is batched with a response message).

The next time the same request is sent from the application (e.g.,mobile application) in step 748, the local proxy 765 now can reply withthe response received from the server cache in step 750. Thus, even inthe event when a cache entry has been invalidated, the application(e.g., mobile application) request need not be sent over the network(e.g., wireless or cellular network) to receive a current/relevantresponse. The subsequent request 752 is sent to the local proxy 765 forprocessing (e.g., forwarded to the application server/content provider795) in step 754.

FIG. 8 depicts a timing diagram showing hunting mode behavior 805 in along poll request and a timing diagram showing timing characteristicswhen the long poll has settled 810.

In hunting mode 805, the request times are held for an increasing amountof time (180, 360 . . . 1024 seconds) until a request times out withoutreceiving a response from the server (as shown in 802, 804, 806, and808). After this time is detected, the request times are now held atsome time less than the time it took for a time out (e.g., now 500seconds) and used to send future long poll requests. The diagram 810shows the timing characteristics of request/response pairs after thelong poll hunting period has settled. These characteristics can bedetected and identified in operation by the local proxy and/or theremote proxy for handling during caching. As previously described, thedistributed caching system can either begin caching (optionally) whilethe application is still in long poll hunting mode or begin cachingafter the hunting period 805 has completed and the application is insettled mode as in 810. In general, if a decrease in time interval isdetected, the response is not cached until the local or remote proxy canverify that a subsequent received response meets cacheabilityconditions.

In general, long poll hunting may or may not be performed by mobile appsor clients but the distributed system includes mechanisms to detect longpoll hunting activity for application long polls and can simply ignorethe long poll hunting requests and begin caching after the huntingperiod has elapsed and the long polls have settled at some constant ornear constant interval value or apply logic to begin caching during thehunting period, thus enabling accelerated caching to enhance performanceand improve user experience.

In process 802, a decision is made to begin to cache content receivedfrom the host server. The decision can be made through the exampleprocesses shown in the example of FIG. 9 which depicts a flow chartillustrating example processes for determining whether to cache contentfrom a particular host server (content source) by determining thefrequency of polling requests made to the host server in step 802 and/orby determining the frequency of content change at the host server instep 804 The two steps can be used in conjunction or independently ofone another in deciding whether content from the host server is to becached, in step 806

In process 804, content from a content server is stored as cachedelements in a local cache on the mobile device. In process 806, apolling request to contact the content server is received by thedistributed caching system. In process 808, if it is determined that aradio of the mobile device is not activated and in process 810, thecached elements are retrieved from the local cache to respond to thepolling request without activating the radio even when a cache defeatingmechanism is employed.

The cache defeat mechanism, or identifiers used intended to defeat cacheaddressed by such identifiers, can be employed by the content server(the server to which the polling requests using the identifiers aredirected). In general, the cache defeating mechanism or identifiersintended for cache defeat can be detected from a syntax or pattern of aresource identifier included in the polling request identifying thecontent server.

For example, the resource identifier can include a URI or URL and theURI/URL is normalized by performing one or more of the following steps:converting the URI scheme and host to lower-case, capitalizing lettersin percent-encoded escape sequences, removing a default port, orremoving duplicate slashes. In addition, the identifier normalizationprocess for an identifier employing cache defeat removes any portion ofthe identifier which is intended to defeat cache (e.g., typically achanging parameter between requests detectable by the format, pattern,or syntax of the parameter).

Note that the detection of cache defeat mechanisms or identifiersintended to defeat cache need not be determined with 100% certainty.Identifiers with certain characteristics (e.g., having parametersmatching specific formats) which can in addition to be determined to beemploying cache defeat may simply be treated as cache defeating orintended for defeating cache for the purposes of caching content over awireless network; for example these may be managed in a distributedfashion.

FIG. 9 depicts an interaction diagram showing how application (e.g.,mobile application) 955 polls having data requests from a mobile deviceto an application server/content provider 995 over a wireless networkcan be can be cached on the local proxy 965 and managed by thedistributed caching system (including local proxy 965 and the hostserver 985 (having server cache 935 or caching proxy server 975)). Theoptional incorporation of keep-alive message management and timing withcache management for HTTP requests are also illustrated.

In one example, when the mobile application/widget 955 polls anapplication server/provider 932, the poll can locally be intercepted 934on the mobile device by local proxy 965. The local proxy 965 can detectthat the cached content is available for the polled content in therequest and can thus retrieve a response from the local cache to satisfythe intercepted poll 936 without requiring use of wireless networkbandwidth or other wireless network resources. The mobileapplication/widget 955 can subsequently receive a response to the pollfrom a cache entry 938.

In another example, the mobile application widget 955 polls theapplication server/provider 940. The poll is intercepted 942 by thelocal proxy 965 and detects that cache content is unavailable in thelocal cache and decides to set up the polled source for caching 944. Tosatisfy the request, the poll is forwarded to the content source 946.The application server/provider 995 receives the poll request from theapplication and provides a response to satisfy the current request 948.In 950, the application (e.g., mobile application)/widget 955 receivesthe response from the application server/provider to satisfy therequest.

In conjunction, in order to set up content caching, the local proxy 965tracks the polling frequency of the application and can set up a pollingschedule to be sent to the host server 952. The local proxy sends thecache set up to the host server 954. The host server 985 can use thecache set up which includes, for example, an identification of theapplication server/provider to be polled and optionally a pollingschedule 956. The host server 985 can now poll the applicationserver/provider 995 to monitor responses to the request 958 on behalf ofthe mobile device. The application server receives the poll from thehost server and responds 960. The host server 985 determines that thesame response has been received and polls the application server 995according to the specified polling schedule 962. The applicationserver/content provider 995 receives the poll and responds accordingly964.

The host server 985 detects changed or new responses and notifies thelocal proxy 965 in step 966. Further in step 966, in conjunction withthe notification of the local proxy 965, host server 985 can also sendkeep-alive related messages 901 (e.g., timing interval or other forms ofinterval indicators) to the mobile client/widget 955 or local proxy 965(e.g., the keep alive related message is batched with the notificationof changed/new response). The host server 985 can additional store thechanged or new response in the server cache or caching proxy 968. Thelocal proxy 965 receives notification from the host server 985 that newor changed data is now available and can invalidate the affected cacheentries 970. The next time the application (e.g., mobileapplication)/widget 955 generates the same request for the sameserver/content provider 972, the local proxy determines that no validcache entry is available and instead retrieves a response from theserver cache 974, for example, through an HTTP connection. The hostserver 985 receives the request for the new response and sends theresponse back in step 976 to the local proxy 965. The request is thussatisfied from the server cache or caching proxy 978 without the needfor the mobile device to utilize its radio or to consume mobile networkbandwidth thus conserving network resources.

Further in step 976, in conjunction with the sending of the newresponse, host server 985 can also send keep-alive related messages 901(e.g., timing interval or other forms of interval indicators) to themobile client/widget 955 or local proxy 965 (e.g., the keep aliverelated message is batched with a response message).

Alternatively, when the application (e.g., mobile application) generatesthe same request in step 980, the local proxy 965, in response todetermining that no valid cache entry is available, forwards the poll tothe application server/provider in step 982 over the mobile network. Theapplication server/provider 995 receives the poll and sends the responseback to the mobile device in step 984 over the mobile network. Therequest is thus satisfied from the server/provider using the mobilenetwork in step 986.

FIG. 10 depicts an interaction diagram showing how application 1055polls for content from an application server/content provider 1095 whichemploys cache-defeating mechanisms in content identifiers (e.g.,identifiers intended to defeat caching) over a wireless network canstill be detected and locally cached. The optional incorporation ofkeep-alive message management and timing with cache management for HTTPrequests are also illustrated.

In one example, when the application (e.g., mobile application)/widget1055 polls an application server/provider in step 1032, the poll canlocally be intercepted in step 1034 on the mobile device by local proxy1065. In step 1034, the local proxy 1065 on the mobile device may alsodetermine (with some level of certainty and heuristics) that a cachedefeating mechanism is employed or may be employed by the serverprovider.

The local proxy 1065 can detect that the cached content is available forthe polled content in the request and can thus retrieve a response fromthe local cache to satisfy the intercepted poll 1036 without requiringuse of wireless network bandwidth or other wireless network resources.The application (e.g., mobile application)/widget 1055 can subsequentlyreceive a response to the poll from a cache entry in step 1038 (e.g., alocally stored cache entry on the mobile device).

In another example, the application (e.g., mobile application) widget1055 polls the application server/provider 1095 in step 1040. The pollis intercepted in step 1042 by the local proxy 1065 which determinesthat a cache defeat mechanism is employed by the server/provider 1095.The local proxy 1065 also detects that cached content is unavailable inthe local cache for this request and decides to setup the polled contentsource for caching in step 1044. The local proxy 1065 can then extract apattern (e.g., a format or syntax) of an identifier of the request andtrack the polling frequency of the application to setup a pollingschedule of the host server 1085 in step 1046.

To satisfy the request, the poll request is forwarded to the contentprovider 1095 in step 1048. The application server/provider 1095receives the poll request from the application and provides a responseto satisfy the current request in step 1050. In step 1052, theapplication (e.g., mobile application)/widget 1055 receives the responsefrom the application server/provider 1095 to satisfy the request.

In conjunction, in order to setup content caching, the local proxy 1065caches the response and stores a normalized version of the identifier(or a hash value of the normalized identifier) in association with thereceived response for future identification and retrieval in step 1054.The local proxy sends the cache setup to the host server 1085 in step1056. The cache setup includes, for example, the identifier and/or anormalized version of the identifier. In some instances, a modifiedidentifier, different from the normalized identifier, is sent to thehost server 1085.

The host server 1085 can use the cache setup, which includes, forexample, an identification of the application server/provider to bepolled and optionally a polling schedule in step 1058. The host server1085 can now poll the application server/provider 1095 to monitorresponses to the request in step 1060 on behalf of the mobile device.The application server 1095 receives the poll from the host server 1085responds in step 1062. The host server 1085 determines that the sameresponse has been received and polls the application server 1095, forexample, according to the specified polling schedule and using thenormalized or modified identifier in step 1064. The applicationserver/content provider 1095 receives the poll and responds accordinglyin step 1066.

This time, the host server 1085 detects changed or new responses andnotifies the local proxy 1065 in step 1068. Further in step 1068, inconjunction with the notification, host server 1085 can also sendkeep-alive related messages 1001 (e.g., timing interval or other formsof interval indicators) to the mobile client/widget 1055 or local proxy1065 (e.g., the keep alive related message is batched with a responsemessage).

The host server 1085 can additionally store the changed or new responsein the server cache 1035 or caching proxy 1075 in step 1070. The localproxy 1065 receives notification from the host server 1085 that new orchanged data is now available and can invalidate the affected cacheentries in step 1072. The next time the application (e.g., mobileapplication)/widget generates the same request for the sameserver/content provider 1095 in step 1074, the local proxy 1065determines that no valid cache entry is available and instead retrievesa response from the server cache in step 1076, for example, through anHTTP connection. The host server 1085 receives the request for the newresponse and sends the response back to the local proxy 1065 in step1078. Further in step 1078, in conjunction with the sending of the newresponse, host server 1085 can also send keep-alive related messages1001 (e.g., timing interval or other forms of interval indicators) tothe mobile client/widget 1055 or local proxy 1065 (e.g., the keep aliverelated message is batched with a response message). The request is thussatisfied from the server cache or caching proxy in step 1080 withoutthe need for the mobile device to utilize its radio or to consume mobilenetwork bandwidth thus conserving network resources.

Alternatively, when the application (e.g., mobile application) 1055generates the same request, the local proxy 1065, in response todetermining that no valid cache entry is available in step 1084,forwards the poll to the application server provider 1095 in step 1082over the mobile network. The application server/provider 1095 receivesthe poll and sends the response back to the mobile device in step 1086over the mobile network. The request is thus satisfied from theserver/provider using the mobile network 1086 in step 1088.

FIG. 11 depicts a flow chart illustrating an example process forcollecting information about a request and the associated response toidentify cacheability and caching the response.

In process 1102, information about a request and information about theresponse received for the request is collected. In processes 1104 and1106, information about the request initiated at the mobile device andinformation about the response received for the request are used inaggregate or independently to determine cacheability at step 1108. Thedetails of the steps for using request and response information forassessing cacheability are illustrated at flow A as further described inthe example of FIG. 12.

In step 1108, if based on flow A it is determined that the response isnot cacheable, then the response is not cached in step 1110, and theflow can optionally restart at 1102 to collect information about arequest or response to again assess cacheability.

In step 1108, if it is determined from flow A that the response iscacheable, then in 1112 the response can be stored in the cache as acache entry including metadata having additional information regardingcaching of the response. The cached entry, in addition to the response,includes metadata having additional information regarding caching of theresponse. The metadata can include timing data including, for example,access time of the cache entry or creation time of the cache entry.

After the response is stored in the cache, a parallel process can occurto determine whether the response stored in the cache needs to beupdated in process 1120. If so, the response stored in the cache of themobile device is invalidated or removed from the cache of the mobiledevice, in process 1122. For example, relevance or validity of theresponse can be verified periodically by polling a host server to whichthe request is directed on behalf of the mobile device. The host servercan be polled at a rate determined at the mobile device using requestinformation collected for the request for which the response is cached.The rate is determined from averages of time intervals between previousrequests generated by the same client which generated the request.Further in process 1122, if an invalidation message was sent from aremote proxy, in conjunction with the sending of the invalidate message,keep-alive related messages 1101 (e.g., timing interval or other formsof interval indicators) can be sent to the mobile client or wirelessdevice (e.g., the keep alive related message is batched with theinvalidation message).

The verifying can be performed by an entity that is physically distinctfrom the mobile device. In one embodiment, the entity is a proxy servercoupled to the mobile device and able to communicate wirelessly with themobile device and the proxy server polls a host server to which therequest is directed at the rate determined at the mobile device based ontiming intervals between previous requests generated by the same clientwhich generated the request.

In process 1114, a subsequent request for the same client or applicationis detected. In process 1116, cache look-up in the local cache isperformed to identify the cache entry to be used in responding to thesubsequent request. In one embodiment, the metadata is used to determinewhether the response stored as the cached entry is used to satisfy thesubsequent response. In process 1118, the response can be served fromthe cache to satisfy a subsequent request. The response can be served inresponse to identifying a matching cache entry for the subsequentrequest determined at least in part using the metadata.

FIG. 12 depicts a flow chart illustrating an example process for adecision flow to determine whether a response to a request can becached.

Process 1202 determines if the request is directed to a blacklisteddestination. If so, the response is not cached, in step 1285. If ablacklisted destination is detected, or if the request itself isassociated with a blacklisted application, the remainder of the analysisshown in the figure may not be performed. The process can continue tosteps 1204 and 1206 if the request and its destination are notblacklisted.

In process 1204, request characteristics information associated with therequest is analyzed. In analyzing the request, in process 1208, therequest method is identified and in step 1214, it is determined whetherthe response can be cached based on the request method. If anuncacheable request is detected, the request is not cached and theprocess may terminate at process 1285. If the request method isdetermined to be cacheable, or not uncacheable, then the response can beidentified as cacheable or potentially cacheable (e.g., cacheable butsubject to the other tests and analysis shown in the figure) at step1295.

In process 1210, the size of the request is determined. In process 1216,it is determined whether the request size exceeds a cacheable size. Ifso, the response is not cached and the analysis may terminate here atprocess 1285. If the request size does not exceed a cacheable size instep 1216, then the response can be identified as cacheable orpotentially cacheable (e.g., cacheable but subject to the other testsand analysis shown in the figure) at step 1295.

In step 1212, the periodicity information between the request and otherrequests generated by the same client is determined. In step 1218, it isdetermined whether periodicity has been identified. If not, the responseis not cached and the analysis may terminate here at process 1285. Ifso, then the response can be identified as cacheable or potentiallycacheable (e.g., cacheable but subject to the other tests and analysisshown in the figure) at step 1295.

In process 1206, the request characteristics information associated withthe response received for the request is analyzed.

In process 1220, the status code is identified and determined whetherthe status code indicates a cacheable response status code in process1228. If an uncacheable status code is detected, the request is notcached and the process may terminate at process 1285. If the responsestatus code indicates cacheability, or not uncacheable, then theresponse can be identified as cacheable or potentially cacheable (e.g.,cacheable but subject to the other tests and analysis shown in thefigure) at step 1295.

In process 1222, the size of the response is determined. In process1230, it is determined whether the response size exceeds a cacheablesize. If so, the response is not cached and the analysis may terminatehere at process 1285. If the response size does not exceed a cacheablesize in step 1230, then the response can be identified as cacheable orpotentially cacheable (e.g., cacheable but subject to the other testsand analysis shown in the figure) at step 1295.

In process 1224, the response body is analyzed. In process 1232, it isdetermined whether the response contains dynamic content or highlydynamic content. Dynamic content includes data that changes with a highfrequency and/or has a short time to live or short time of relevance dueto the inherence nature of the data (e.g., stock quotes, sports scoresof fast pace sporting events, etc.). If so, the response is not cachedand the analysis may terminate here at process 1285. If not, then theresponse can be identified as cacheable or potentially cacheable (e.g.,cacheable but subject to the other tests and analysis shown in thefigure) at step 1295.

Process 1226 determines whether transfer encoding or chunked transferencoding is used in the response. If so, the response is not cached andthe analysis may terminate here at process 1285. If not, then theresponse can be identified as cacheable or potentially cacheable (e.g.,cacheable but subject to the other tests and analysis shown in thefigure) at step 1295.

Not all of the tests described above need to be performed to determinedwhether a response is cached. Additional tests not shown may also beperformed. Note that any of the tests 1208, 1210, 1212, 1220, 1222,1224, and 1226 can be performed, singly or in any combination todetermine cacheability. In some instances, all of the above tests areperformed. In some instances, all tests performed (any number of theabove tests that are actually performed) need to confirm cacheabilityfor the response to be determined to be cacheable. In other words, insome cases, if any one of the above tests indicate non-cacheability, theresponse is not cached, regardless of the results of the other tests. Inother cases, different criteria can be used to determine which tests orhow many tests need to pass for the system to decide to cache a givenresponse, based on the combination of request characteristics andresponse characteristics.

FIG. 13 depicts a flow chart illustrating an example process fordetermining potential for cacheability based on request periodicityand/or response repeatability.

In process 1302, requests generated by the client are tracked to detectperiodicity of the requests. In process 1306, it is determined whetherthere are predictable patterns in the timing of the requests. If so, theresponse content may be cached in process 1395. If not, in process 1308it is determined whether the request intervals fall within a tolerancelevel. If so, the response content may be cached in process 1395. Ifnot, the response is not cached in process 1385.

In process 1304, responses received for requests generated by the clientare tracked to detect repeatability in content of the responses. Inprocess 1310, hash values of response bodies of the responses receivedfor the client are examined and in process 1312 the status codesassociated with the responses are examined. In process 1314, it isdetermined whether there is similarity in the content of at least two ofthe responses using hash values and/or the status codes. If so, theresponse may be cached in process 1395. If not, the response is notcached in 1385.

FIG. 14 depicts a flow chart illustrating an example process fordynamically adjusting caching parameters for a given request or client.

In process 1402, requests generated by a client or directed to a hostare tracked at the mobile device to detect periodicity of the requests.Process 1404 determines if the request intervals between the two or morerequests are the same or approximately the same. In process 1406, it isdetermined that the request intervals between the two or more requestsfall within the tolerance level.

Based on the results of steps 1404 and 1406, the response for therequests for which periodicity is detected is received in process 1408.

In process 1412, a response is cached as a cache entry in a cache of themobile device. In process 1414, the host is monitored at a rate toverify relevance or validity of the cache entry, and simultaneously, inprocess 1416, the response can be served from the cache to satisfy asubsequent request.

In process 1410, a rate to monitor a host is determined from the requestinterval, using, for example, the results of processes 1404 and/or 1406.In process 1420, the rate at which the given host is monitored is set toverify relevance or validity of the cache entry for the requests. Inprocess 1422, a change in request intervals for requests generated bythe client is detected. In process 1424, a different rate is computedbased on the change in request intervals. The rate at which the givenhost is monitored to verify relevance or validity of the cache entry forthe requests is updated in step 1420.

FIG. 15 depicts a flow diagram 1500 illustrating an example process forusing request intervals to determine and to set a polling interval orrate at which a proxy server is to monitor an application server/contenthost on behalf of the mobile device.

The flow diagram 1500 refers to various timing parameters ofrequest/response sequences, shown diagrammatically in FIG. 17A-B. Thetiming parameters ‘IT,’ ‘RI,’ ‘D,’ ‘RT’ are defined as follows andillustrated in FIG. 17A-B.

1. RI—Request interval—Time between “Request Sent 0” and “Request Sent1.”

2. D—Delay—Time between ‘Request sent’ and “First bytes of response(HEADER) arrived.”

3. IT—Idle time—Time between ‘Whole Response content received 0’ and‘Request Sent 1’.

4. RT—Response time—Time between “First bytes of response (HEADER)arrived.” and ‘Whole Response content received.’

When the local proxy sets up a poll with the proxy server, the pollinginterval or rate can be specified via timing parameters RI, IT, D, orany combination of the above. Some examples of ways the local proxy cansetup a poll with the proxy includes: a) specifying IT only—which can beused in case of stable IT intervals; b) specifying IT and D—this can beused in the case of stable IT and long D; c) RI only—in the case ofstable RI (e.g., detected linear pattern); and d) RI and D—this may beused in the case of stable RI and long D.

Each of the setups can be selected based on the criteria shown in theflow diagram, starting at step 1502 where it is determined whether ITfor a request of a given client/application (e.g., mobile application)is stable. If IT is not stable, in process 1512, it is determinedwhether RI is periodic and if not, no pattern has been detected yet instep 1520. RI is periodic, then the process continues to step 1522, asdetailed below.

If IT is stable at 1502, it is determined whether ‘IT’ is zero in step1504. If ‘IT’ is not zero at step 1504, it is determined whether ‘RI’ ismore stable than ‘IT’ in step 1514. If not, the process continues to1506. If so, the process proceeds to determine whether ‘D’ is stable orif long poll hunting pattern is detected in step 1522. If not, then thepoll is setup for polling with ‘RI’ in step 1526. If at step 1522 D isstable and hunting pattern is detected, the process continues at step1524 to determine whether ‘D’ is long, and if so, the poll is setup withboth ‘RI’ and “D.’ If not, the poll is just set up with ‘RI in process1526.

If ‘IT’ is detected to be zero at 1504, in step 1506 it is thendetermined whether ‘D’ is stable or if a hunting pattern (for a longpoll) is detected. If so, in step 1508 it is determined whether ‘ID’ islong, and if so, in step 1510 the intervals of ‘ID’ and ‘IT’ can be usedfor polling. As such the determined ‘D’ and/or ‘IT’ can be specified tothe proxy server, or other entity monitoring the content source onbehalf of the mobile device or local proxy. If ‘ID’ is determined to notbe long in step 1508, the poll can be setup with just ‘IT’ in step 1518.However, if at 1506, ‘D’ is not detected to be stable and a huntingpattern is not detected, then no pattern has been detected as yet, as instep 1516.

A ‘stable’ interval can generally be used to refer to some level ofrepeatability or predictability in the interval within some tolerablethreshold between two or more requests. For example, ‘stable’ could meanthat two intervals are within 5%, 10%, 15%, or 20% of one another. Insome instance, a larger differential may also be allowed. The thresholdused to quality a ‘stable’ interval could be a static value or it couldbe a dynamic value which changes with real-time operating conditions,and/or a value which is varying based on device, user, OS, application,network operator, ISP, and/or other third party specifications, Nostringent definition for ‘stable’ needs to be applied so long as thespecified intervals used for polling of the proxy server on behalf ofthe mobile device does not significantly negatively impact the user'sperception of performance or user experience.

FIG. 16 depicts example timing diagrams 1600 showing timingcharacteristics for various types of request-response sequences.

In FIG. 16, 8 time line combinations are illustrated, each containing 2blocks of request-response sequences. In each sequence, the dotted lineindicates a response in a request-response interval. Sequence 1602 ischaracterized by a short ‘D’, short ‘RT’, and long ‘IT’. Thus sequence1602 may be a typical poll. Sequence 1604 is characterized by a short‘D’, a short ‘RT’, a short ‘IT’ and is indicative of a high pollingrate. Sequence 1604 may also indicate that a user is activelyinteracting with the application and/or actively refreshing theapplication.

Sequence 1606 is characterized by a short ‘D’, a long ‘RT’ and short‘IT,’ which can indicate possible streaming. Sequence 1608 ischaracterized by a short 1Y, a long ‘RT, and a long ‘IT’ which canindicate polling of large content. Sequence 1610 is characterized by along  D,’ a short ‘RT,’ and a long ‘IT, which may indicate a long pollwith high latency allowed on the application level.

Sequence 1612, which has a long ‘D’, a short ‘RT’, and a short ‘IT’ mayindicate a long poll. Sequence 1614, having a long ‘D’, long ‘RT’ andshort ‘IT’ can indicate streaming or long poll of large content.Sequence 1616 has a long ‘D’ a ‘long ‘RT’, and long ‘IT’ can be acombination of 1614 and 1610.

FIG. 17A depicts an example of a timing diagram 1700 showing timingcharacteristics for request and response sequences.

The present technology includes a distributed caching model whichinvolves cooperation of the device-side proxy and server-side. In orderfor it to work after caching a response, the client-side component needsto notify the server-side proxy and also provide a rate that aparticular resource (application server/content provider) must be polledat (to verify validity of cached content). After receiving thisnotification, the server-side proxy can then monitor the resource forchanges (validating resource), and once a change is detected, theserver-side component can notify the device-side component by sending aninvalidation request.

The client-side component needs to provide a correct and suitablepolling interval to the server-side proxy (e.g., the interval at whichthe server-side proxy is polling the resource to monitor it) for optimalperformance, since if the polling interval is too low, the load isunnecessarily increased on the server-side proxy. By increasing thepolling interval, the local proxy risks providing the expired/irrelevantinformation to the user at the user device.

As previously described, timing characteristics of request-responsessequences between a requesting client/application and contentprovider/application server can be used to determine applicationbehavior and/or to categorize request type. Such information can be usedto determine, identify, estimate, or predict an application's pollingintervals such that an optimal polling interval at which server-sideproxy needs to monitor the resource can be determined and provided tothe server-side proxy.

The timing characteristics can include, for example, response/delay timeto receive a response after a request has been sent and an idle time tosend a subsequent request after the response has been received. Therelationships of the various time intervals in a response-requestsequence can be seen in the timing diagram 1700.

Each request-response time sequence can be described using all or someof the following events: 1) Start sending request (1705); 2) Requestsent; 3) Response start (1710); 4) Response end (1720); and 5) Nextrequest send (1715). The ‘Response Start’ 1710) indicates when the firstbytes of response (HEADER) arrived and the ‘Response end 1720’ indicateswhen all response content has been received.

Using these events, the device-side can calculate the followingintervals shown in 1700:

1. RI 1708—Request interval—Time between “Request Sent 0” and “RequestSent 1.”

2. D 1704—Delay—Time between ‘Request sent’ and “First bytes of response(HEADER) arrived.”

3. IT 1706—Idle time—Time between ‘Whole Response content received 0’and ‘Request Sent 1’

4. RT 1712—Response time—Time between “First bytes of response (HEADER)arrived.” and ‘Whole Response content received”

The relationship of the timing characteristic in a request-responsesequence (RI=D+RT+IT) can be considered to extract application behaviorinformation for use in caching content in a distributed fashion.Relative comparisons between different intervals can also be used tocharacterize the application and its requests.

In general, the device-side component of the distributed proxy can keeptrack of individual timing intervals in a request-response sequence andcompare the values in a relative (e.g., bigger or smaller than anotherinterval) or absolute manner (specific duration, long, short compared toa dynamic or static threshold value, etc.). The device-side componentcan track these interval values over time, check for stable componentsand determine or identify tendencies or patterns. For example, thedevice-side component can detect increasing or decreasing ‘D’ 1704 inthe case of long poll hunting mode for long poll requests. FIG. 17Bdepicts an example of a timing diagram 1750 showing timingcharacteristics for request/response sequences characteristic of a longpoll. Note that timing diagram 1750 may not be applicable to highlatency long polls.

In one embodiment, a request can be detected, determined, or to be along poll request based on a comparison of the response/delay time (D1754) relative to the idle time (IT 1756) between request 0 1755 andresponse start time 1760. For example, the request can be detected to bea long poll request when the idle time is short compared to the responsedelay time (IT 1756<D 1754). The request can also be determined to be along poll when IT 1756 is zero or substantially zero (˜0).

In addition, the request can be determined or categorized as a long pollrequest if the idle time (IT 1756) indicates an immediate ornear-immediate issuance of the subsequent request after receipt of theresponse (e.g., a short IT 1756). In addition, a request can bedetermined to be a long poll if RI 1758=D 1754+RT 1762+IT 1756˜D 1754+RT1762. In one embodiment, the response time ‘RT’ 1762 can be used todetermine bit rate (e.g., size in byte*8/time).

In general, different combinations of time intervals provide indicationsabout polling pattern of the specific application or request and can beused by the device-side component to generate a polling interval for theserver-side component to use in monitoring the content source.

FIG. 18 depicts a data timing diagram 1800 showing an example ofdetection of periodic request which may be suitable for caching.

In the example shown, a first request from a client/application on amobile device is detected at time 1:00 (t1). At this time, a cache entrymay be created in step 1802. At time 2:00 (t2), the second request isdetected from the same client/application, and the cache entry that wascreated can now be updated with the detected interval of 1 hour betweentime t2 and t1 at step 1804. The third request from the same client isnow detected at time t3=3:00, and it can now be determined that aperiodic request is detected in step 1806. The local proxy can now cachethe response and send a start poll request specifying the interval(e.g., 1 hour in this case) to the proxy server.

The timing diagram further illustrates the timing window between 2:54and 3:06, which indicates the boundaries of a window within whichperiodicity would be determined if the third request is received withinthis time frame 1810. The timing window 1808 between 2:54 and 3:06corresponds to 20% of the previous interval and is the example toleranceshown. Other tolerances may be used, and can be determined dynamicallyor on a case by case (application by application) basis.

FIG. 19 depicts a data timing diagram 1900 showing an example ofdetection of change in request intervals and updating of server pollingrate in response thereto.

At step 1902, the proxy determines that a periodic request is detected,the local proxy caches the response and sets the polling request to theproxy server, and the interval is set to 1 hour at the 3rd request, forexample. At time t4=3:55, the request is detected 55 minutes later,rather than 1 hour. The interval of 55 minutes still fits in to thewindow 1904 given a tolerance of 20%. However, at step 1906, the 5threquest is received at time t5=4:50, which no longer fits within thetolerance window set determined from the interval between the 1st andsecond, and second and third requests of 1 hour. The local proxy nowretrieves the resource or response from the proxy server, and refreshesthe local cache (e.g., cache entry not used to serve the 5th request).The local proxy also resends a start poll request to the proxy serverwith an updated interval (e.g., 55 minutes in the example) and thewindow defined by the tolerance, set by example to 20%, now becomes 11minutes, rather than 12 minutes.

Note that in general, the local proxy notifies the proxy server with anupdated polling interval when an interval changes is detected and/orwhen a new rate has been determined. This is performed, however,typically only for background application requests orautomatic/programmatic refreshes (e.g., requests with no userinteraction involved). In general, if the user is interacting with theapplication in the foreground and causing out of period requests to bedetected, the rate of polling or polling interval specified to the proxyserver is typically not update, as illustrated in FIG. 20. FIG. 20depicts a data timing diagram 2000 showing an example of servingforeground requests with cached entries.

For example, between the times of t=3:00 and 3:30, the local proxydetects 1st and 2nd foreground requests at t=3:10 and t=3:20. Theseforeground requests are outside of the periodicity detected forbackground application or automatic application requests. The responsedata retrieved for the foreground request can be cached and updated,however, the request interval for foreground requests are not sent tothe server in process 2008.

As shown, the next periodic request detected from the application (e.g.,a background request, programmatic/automatic refresh) at t=4:00, theresponse is served from the cache, as is the request at t=5:00.

FIG. 21 depicts a data timing diagram 2100 showing an example of anon-optimal effect of cache invalidation occurring after outdatedcontent has been served once again to a requesting application.

Since the interval of proxy server polls is set to approximately thesame interval at which the application (e.g., mobile application) issending requests, it is likely the case that the proxy server typicallydetects changed content (e.g., at t=5:02) after the cached entry (nowoutdated) has already been served for a request (e.g., to the 5threquest at t=5:00). In the example shown, the resource updates orchanges at t=4:20 and the previous server poll which occurs at t=4:02was not able to capture this change until the next poll at 5:02 andsends a cache invalidation to the local proxy at 2110. Therefore, thelocal cache does not invalidate the cache at some time after the 5threquest at time t=5:00 has already been served with the old content. Thefresh content is now not provided to the requesting application untilthe 6th request at t=6:00, 1 period later at process 2106.

To optimize caching performance and to resolve this issue, the localproxy can adjust time setup by specifying an initial time of request, inaddition to the polling interval to the proxy server. The initial timeof request here is set to some time before (e.g., a few minutes) therequest actually occurred such that the proxy server polls occurslightly before actual future application requests. This way, the proxycan pick up any changes in responses in time to be served to thesubsequent application request.

FIG. 22 depicts a data timing diagram 2200 showing cache management andresponse taking into account the time-to-live (TTL) set for cacheentries.

In one embodiment, cached response data in the local cache specifies theamount of time cache entries can be stored in the local cache until itis deleted or removed.

The time when a response data in a given cache entry is to be removedcan be determined using the formula: <response data cache time>+<TTL>,as shown at t=3:00, the response data is automatically removed after theTTL has elapsed due to the caching at step 2212 (e.g., in this example,24 hours after the caching at step 2212). In general the time to live(TTL) applies to the entire cache entry (e.g., including both theresponse data and any metadata, which includes information regardingperiodicity and information used to compute periodicity). In oneembodiment, the cached response data TTL is set to 24 hours by defaultor some other value (e.g., 6 hours, 12 hours, 48 hours, etc.). The TTLmay also be dynamically adjustable or reconfigured by the admin/userand/or different on a case-by-case, device, application, networkprovider, network conditions, operator, and/or user-specific basis.

FIG. 23 depicts a diagram of an example of the component API layer forthe cache store.

One example of the cache store component API layer can include thefollowing entities: 1) Cache Manager 2312. Client facing entry point tothe cache management system. This can allow registration of differentcaches for multiple applications/clients, providing them to relevantapplications/clients when required. 2) ICache 2314. This entityrepresents a cache store, i.e., a mechanism for maintaining a pool ofcache entries. Cache entries in the iCache can be queried, edited,removed, and/or updated with new entries. 3) ICacheListener 2304. Thisallows implementation of features in application/clients to enablereceipt of cache related notifications. 4) CacheEvent 2302. Thisrepresents a cache related event. 5) Iterator 2320. This provides amechanism for iterating on a collection of cache entries. 6)ICacheFilter 2306. This provides a mechanism for filtering cacheentries. 7) UrlFilter 2308. This is a cache filter that allowsperforming cache lookups based on entry URIs. 8) IdentityFilter 2310.This is a cache filter that allows performing cache lookups based onentry IDs. 9) ICacheEntry 2316. This entity represents a single cacheentry. Cache entry is identified either by ID or by URI; both generallymust be unique in scope of a single cache. 10) ICacheEntryData 2318.This is a named data associated with some cache entry.

FIG. 24 depicts a diagram showing one example of the data model for thecache store. Cache stores may be mobile platform specific. In oneembodiment, cache stores can utilize hybrid storage, which can includethe following components: 1) SQL file database for persisting cacheentries, or 2) file system for persisting meta-data and binary responsedata. This configuration can be used for mobile platforms such asAndroid.

FIG. 25 depicts a conceptual diagram of one example of the data model ofa cache entry 2504 in the cache store 2502. A given cache entry 2504 canbe identified by an identifier (e.g., URI). In general, cache entriesinclude a response data component (e.g., ResponseData field 2508) andany associated metadata (e.g., MetaInfo field 2506).

FIG. 26A-B depicts example request-response pairs showing cacheableresponses 2604 and 2654 addressed by identifiers with changingparameters 2602 and 2652.

The request/response pairs shown in the examples of FIG. 26A illustratetiming parameters 2602 used for cache defeat since the responses 2604received for each request is the same even though the timing parameters2602 change each time. The resource identifier and the parameter 2602can be identified as cache defeating upon the second time the ‘response’is detected to be the same, or the third time, or a later subsequenttime. The caching of the ‘response=x’ can similarly begin the seconddetected same response, the third detected same response, or a latersubsequent detected same response.

Similarly, the request response pairs shown in the examples of FIG. 26Billustrate random parameters 2652 that are used for cache defeat sincethe responses 2654 received for each request is the same even though therandom parameters 2652 in the identifiers are varying each time. Theresource identifier and the parameter 2602 can be identified as cachedefeating upon the second time the ‘response’ is detected to be thesame, or the third time, or a later subsequent time. The caching of the‘response=x’ can similarly begin the second detected same response, thethird detected same response, or a later subsequent detected sameresponse.

Although two types of changing parameters are shown (timing/date 2602and random parameter 2652), other types of changing parameters may beused for cache defeat and can be similarly detected by the system.

FIG. 27 depicts a diagram showing various options for batching thesending of keep-alive messages and/or related indicators with othermessages in a mobile network and/or in a distributed caching system.

Keep alive messaging between a mobile device 2750 and a host server 2700(or a proxy server 2725 associated with the host server 2700) can takeplace via various communication channels via batching with othermessages or in standalone fashion. For example, a keep-alive message toindicate health or operational status of the host server 2700 and/orproxy 2725 can be sent by itself 2702. The keep-alive message can alsobe sent with a timing interval or an indicator of interval between themessages 2704.

The timing intervals or interval indicators may be sent on their own2706, or with a cache-related message 2710. A cache-related message caninclude messages include update cache entries on the mobile device 2750,messages indicating that one or more cache entries on mobile device 2750are irrelevant or outdated, for example. The use of batching ofkeep-alive messages with their related indicators (e.g., timing orotherwise) can further reduce the consumption of mobile networkresources and mobile device battery power.

FIG. 28 depicts an example of a timing diagram 2800 showing the timingof keep-alive messages in response to changes in polling intervals.

Polls sent from a device (e.g., mobile device 250) are detected at 2802,2804, 2806, 2808 at relatively constant intervals 2852. Since the pollsconstitute fairly regular communications with a content host or proxyserver, a keep-alive mechanism may not yet be needed as a statusindicator of health among the entities in communication with oneanother.

However, when the poll requests slow down (e.g., polls 2810 and poll2814), the gap in communications may become long enough that the serverneeds to send a keep-alives (e.g., keep alive messages 2812, 2816, 2818,2820, etc.) or other messages to maintain the mobile device or mobileclient's trust in the server's health.

Initially, the keep-alive interval (e.g., Interval A 2858) may be basedon a polling rate. For example, assume there are multiple resourcesbeing polled on the server side with different polling intervals. Thefirst heartbeat interval may be based on the smallest (shortest) pollinginterval and is communicated to the client in the acknowledgement to thelast polling request. In some embodiments, the interval can beconfigured so that it is 0.5, 1 or 2 (or N) times the smallest pollinginterval.

In addition to the average communication (e.g., polling) rate,determining when to generate a keep-alive message may also factor in theaverage deviation of the communication rate. The deviation or averagedeviation can be computed as soon as the server starts communicatingcontent changes to the client or mobile device side. Assume the timeinterval between two communication events from server to client isidentified as (t), with t_(avg) being the average value of suchinterval. The average deviation of the actual intervals from t_(avg) isd_(avg).

In this scenario, using the concept of “trust” or reliance on theserver's health and proper operation and functioning:

-   -   The client or wireless/mobile device can have full trust of the        server until the time from previous communication reaches        t_(avg)    -   The client should have adequate trust of the server until the        time reaches t_(avg)+d_(avg)    -   (1) should reset the interval with the first data package going        out.

In some embodiments, beyond this point the delay from a previouscommunication becomes exceptionally (or at least unacceptably) long, andthe server should send a heartbeat message (or similar form ofcommunication) to maintain the client's trust in the server's health(e.g., its proper functional and/or operational status).

In practice, once the client receives a heartbeat from the server, itshould set its expectation for the next communication event based on thetimestamp in the heartbeat message, not on the historical rate ofchanges which were driven by the actual data sources. The fact that aheartbeat gets sent means that there was a sufficient change in the rateof changes and the server is sending the heartbeat message(s) to bridgethe gap.

As mentioned, typically the interval between a last data communicationand a first keep alive message can be based on statistics of thecommunication intervals in the past. In some embodiments, immediatelyafter sending a first keep-alive message the server should startincreasing that interval relatively aggressively as shown by Interval B2860 and Interval C 2862.

This can be performed because:

-   -   (2) If there has really been a dramatic change in the average        rate of communication from server to client, then the server        should adapt to the new level with as few heartbeat messages as        possible; and    -   (3) If there hasn't been an actual change in the rate of        communication and the keep-alive was sent out due to a random        spike in the interval value, then the server can detect and        identify the spike and reset the interval with the next data        package going out to the mobile client or device.

In some embodiments, an aggressive increase in the keep-alive intervalcan be achieved by multiplying the current keep-alive interval with aconstant, or exponentially increasing the interval, or adding a constantvalue on top of it. Multiplying the interval makes the growthexponential instead of linear and is a fast yet predictable way ofbridging the communication gap.

FIG. 29 depicts a flow chart illustrating an example process fordynamically adapting the use of keep-alive messaging and/or timingthere-between based on rates of data communications of a mobile device(wireless device).

In process 2902, a rate of content polls is determined at the mobiledevice. In process 2904, a content change rate at which content at asource changes is detected. The content at the source can be polled bythe mobile device.

In process 2906, rates of data communications between a mobile deviceand a proxy server are monitored. In one embodiment, the rate ofcommunication is determined using the content change rate and/or therate of content polls. The process is further detailed from the exampleflow of FIG. 31. In some instances, the content polls can include pollsdirected to multiple resources with different polling rates and when thekeep-alive message is sent, can be determined using a smallest pollinginterval among the different polling rates.

In process 2908, a decrease in the rates of data communications betweenthe mobile device and the proxy server is detected. In process 2910, itis detected that communication with the mobile device has been dormantfor a time period due to the decrease in the rates of datacommunications. In process 2912, a keep-alive message is sent to themobile device. In process 2914, subsequent keep-alive messages are sentto the mobile device at increasing intervals between the successivekeep-alive messages.

In process 2916, the system indicates to the mobile device that thesubsequent keep-alive messages will be sent at increased intervals.Various ways to batch messages with timing indications are furtherillustrated at flow ‘A’ in FIG. 30. Note that the increasing of theintervals can occur in any known or convenient fashion. In oneembodiment, increasing the intervals between the subsequent periodicmessages is performed in a multiplicative or geometric fashion toexpedite the increase.

In process 2918, the number of keep-alive messages used to signaloperational status can be decreased. In one embodiment, the indicationsto the mobile device that the subsequent keep-alive messages will besent at increased intervals with are can be sent with one or more of thesubsequent keep-alive messages. Alternatively, the indications to themobile device that the subsequent keep-alive messages will be sent atincreased intervals can be with acknowledgements or responses to contentpolls. Similarly, an indication of timing of the subsequent keep-alivemessages can be sent with a cache-related message.

FIG. 30 depicts a flow chart illustrating an example process forbatching keep-alive messages sent to a mobile client or wireless deviceand decreasing the number of keep-alive messages that are sent.

In process 3000, the system indicates to the mobile device that thesubsequent keep-alive messages will be sent at increased intervals.These indications can be sent via various mechanisms, some involvingbatching with other messages sent to the mobile device to minimizenetwork resources consumed for signaling.

For example, as an alternative or in addition to sending indications ofintervals by itself in its own message in step 3002, indications ofintervals with one or more of the keep-alive messages in process 3004.Indications of intervals can also be sent with acknowledgements orresponses to content polls in step 3006. Similarly, an indication oftiming of the subsequent keep-alive messages can also be sent with acache-related message in step 3008. Examples of various ways forbatching keep-alive messaging and related indicators (e.g., timingindicators) between a mobile device and a server (e.g., a proxy server)are illustrated diagrammatically in the example of FIG. 27.

FIG. 31 depicts a flow chart illustrating an example process forcomputing timing intervals between keep-alive messages based on rate ofcommunication at a mobile client or wireless device.

In process 3102, the rate of communication is determined. In process3104, an average rate of communication is determined. In process 3106, astandard deviation is determined for the average rate. In process 3108,the increasing intervals between the subsequent keep-alive messages arecomputed using the average rate of communication and the standarddeviation of the average rate.

FIG. 32 depicts a flow chart illustrating an example process for usingan initial value for a time interval between keep-alive messages andadjusting the initial value based on subsequent rates of communicationsbetween a mobile device and a proxy server.

In process 3202, an initial value for a time interval between keep-alivemessages is determined based on a rate of content polls on a mobiledevice. In process 3203, subsequent rates of communications between themobile device and a proxy server are monitored. In one embodiment, akeep-alive message is sent to the mobile device after communication withthe mobile device has been dormant for a time period. The dormancy canbe detected by the proxy server and in some instances, the keep-alivemessages are generated and sent by the proxy server.

In process 3204, the initial value of the time interval is dynamicallyadjusted to an updated value based on the rate of communication. Theupdated value may be determined by the proxy server and/or userconfigured/re-configured.

FIG. 33 depicts a flow chart illustrating an example process fordecreasing the number of periodic messages needed to indicate healthfulstatus of network components and intelligently acknowledging mobileclients of the decreasing timing intervals.

In process 3302, the system engages in a data communication session witha mobile client. The data communication session can includerequest-responses between the mobile client (e.g., a mobile applicationor widget) on a mobile device and a proxy server or host server to whichthe requests are directed.

In process 3304, communication intervals of data communications with themobile client is determined. Communication intervals can be determinedby, for example, a local proxy on the mobile device based on rate ofpolling requests directed to the content source. Data communicationswith the mobile client can also be in part determined from rate ofcontent change at the content source to which application or HTTPrequests are directed.

In process 3306, a timing of when a periodic message is to be sent isdetermined based on communication intervals past data communication withthe mobile device. In process 3308, a periodic message is sent over thewireless network to a mobile client to indicate healthful status basedon the timing. In process 3310, the periodic message is sent with atiming parameter to indicate to the mobile client, when a next periodicmessage is to be sent.

In process 3312, subsequent periodic messages are sent after theperiodic message to the mobile client at increasing time intervals. Inone embodiment, a rate of content change of content to be delivered tothe mobile client in the data communication session is detected at acontent source and timing between the subsequent periodic messages canbe set or adjusted based on the rate of content change.

In general, subsequent periodic messages after the periodic message toindicate operational state are sent to the mobile client in a mannerthat conserves use of the mobile network and/or in a manner that limitsconsumption of battery life of the mobile device. For example, periodicmessages and/or related signaling can be batched with other messagesthat need to be sent to the mobile client.

For example, a keep-alive message and/or one or more of its associatedtiming parameters can be sent in a message containing content (e.g., aresponse to a request initiated at the mobile client). The keep aliveand/or the associated timing parameters can also be sent with acache-related message (e.g., a cache update, or cache invalidatemessage). The associated timing parameters can include a timingparameter to indicate when a next periodic message for indicatingoperational state is to be expected, for example and can be sent eitherwith a periodic keep-alive message itself and/or with other messages(e.g., responses, or cache-related messages) sent to the mobile clientto reduce signaling needs.

FIG. 34 shows a diagrammatic representation of a machine 3400 in theexample form of a computer system within which a set of instructions,for causing the machine to perform any one or more of the methodologiesdiscussed herein, may be executed.

In alternative embodiments, the machine operates as a standalone deviceor may be connected (e.g., networked) to other machines. In a networkeddeployment, the machine may operate in the capacity of a server or aclient machine in a client-server network environment, or as a peermachine in a peer-to-peer (or distributed) network environment.

The machine may be a server computer, a client computer, a personalcomputer (PC), a user device, a tablet PC, a laptop computer, a set-topbox (STB), a personal digital assistant (PDA), a cellular telephone, aniPhone, an iPad, a Blackberry, a processor, a telephone, a webappliance, a network router, switch or bridge, a console, a hand-heldconsole, a (hand-held) gaming device, a music player, any portable,mobile, hand-held device, or any machine capable of executing a set ofinstructions (sequential or otherwise) that specify actions to be takenby that machine.

While the machine-readable medium or machine-readable storage medium isshown in an exemplary embodiment to be a single medium, the term“machine-readable medium” and “machine-readable storage medium” shouldbe taken to include a single medium or multiple media (e.g., acentralized or distributed database and/or associated caches andservers) that store the one or more sets of instructions. The term“machine-readable medium” and “machine-readable storage medium” shallalso be taken to include any medium that is capable of storing, encodingor carrying a set of instructions for execution by the machine and thatcause the machine to perform any one or more of the methodologies of thepresently disclosed technique and innovation.

In general, the routines executed to implement the embodiments of thedisclosure may be implemented as part of an operating system or aspecific application, component, program, object, module or sequence ofinstructions referred to as “computer programs.” The computer programstypically comprise one or more instructions set at various times invarious memory and storage devices in a computer that, when read andexecuted by one or more processing units or processors in a computer,cause the computer to perform operations to execute elements involvingthe various aspects of the disclosure.

Moreover, while embodiments have been described in the context of fullyfunctioning computers and computer systems, those skilled in the artwill appreciate that the various embodiments are capable of beingdistributed as a program product in a variety of forms, and that thedisclosure applies equally regardless of the particular type of machineor computer-readable media used to actually effect the distribution.

Further examples of machine-readable storage media, machine-readablemedia, or computer-readable (storage) media include but are not limitedto recordable type media such as volatile and non-volatile memorydevices, floppy and other removable disks, hard disk drives, opticaldisks (e.g., Compact Disk Read-Only Memory (CD ROMS), Digital VersatileDisks, (DVDs), etc.), among others, and transmission type media such asdigital and analog communication links.

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words “comprise,” “comprising,” and thelike are to be construed in an inclusive sense, as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to.” As used herein, the terms “connected,”“coupled,” or any variant thereof, means any connection or coupling,either direct or indirect, between two or more elements; the coupling ofconnection between the elements can be physical, logical, or acombination thereof. Additionally, the words “herein,” “above,” “below,”and words of similar import, when used in this application, shall referto this application as a whole and not to any particular portions ofthis application. Where the context permits, words in the above DetailedDescription using the singular or plural number may also include theplural or singular number respectively. The word “or,” in reference to alist of two or more items, covers all of the following interpretationsof the word: any of the items in the list, all of the items in the list,and any combination of the items in the list.

The above detailed description of embodiments of the disclosure is notintended to be exhaustive or to limit the teachings to the precise formdisclosed above. While specific embodiments of, and examples for, thedisclosure are described above for illustrative purposes, variousequivalent modifications are possible within the scope of thedisclosure, as those skilled in the relevant art will recognize. Forexample, while processes or blocks are presented in a given order,alternative embodiments may perform routines having steps, or employsystems having blocks, in a different order, and some processes orblocks may be deleted, moved, added, subdivided, combined, and/ormodified to provide alternative or sub-combinations. Each of theseprocesses or blocks may be implemented in a variety of different ways.Also, while processes or blocks are at times shown as being performed inseries, these processes or blocks may instead be performed in parallel,or may be performed at different times. Further any specific numbersnoted herein are only examples: alternative implementations may employdiffering values or ranges.

The teachings of the disclosure provided herein can be applied to othersystems, not necessarily the system described above. The elements andacts of the various embodiments described above can be combined toprovide further embodiments.

Any patents and applications and other references noted above, includingany that may be listed in accompanying filing papers, are incorporatedherein by reference. Aspects of the disclosure can be modified, ifnecessary, to employ the systems, functions, and concepts of the variousreferences described above to provide yet further embodiments of thedisclosure.

These and other changes can be made to the disclosure in light of theabove Detailed Description. While the above description describescertain embodiments of the disclosure, and describes the best modecontemplated, no matter how detailed the above appears in text, theteachings can be practiced in many ways. Details of the system may varyconsiderably in its implementation details, while still beingencompassed by the subject matter disclosed herein. As noted above,particular terminology used when describing certain features or aspectsof the disclosure should not be taken to imply that the terminology isbeing redefined herein to be restricted to any specific characteristics,features, or aspects of the disclosure with which that terminology isassociated. In general, the terms used in the following claims shouldnot be construed to limit the disclosure to the specific embodimentsdisclosed in the specification, unless the above Detailed Descriptionsection explicitly defines such terms. Accordingly, the actual scope ofthe disclosure encompasses not only the disclosed embodiments, but alsoall equivalent ways of practicing or implementing the disclosure underthe claims.

While certain aspects of the disclosure are presented below in certainclaim forms, the inventors contemplate the various aspects of thedisclosure in any number of claim forms. For example, while only oneaspect of the disclosure is recited as a means-plus-function claim under35 U.S.C. §112, ¶6, other aspects may likewise be embodied as ameans-plus-function claim, or in other forms, such as being embodied ina computer-readable medium. (Any claims intended to be treated under 35U.S.C. §112, ¶6 will begin with the words “means for.”) Accordingly, theapplicant reserves the right to add additional claims after filing theapplication to pursue such additional claim forms for other aspects ofthe disclosure.

1. A system for optimizing resources used for keep-alive messagesignaling in a mobile network, the system, comprising: a local proxy ona mobile device; a proxy server coupled to a content source, the proxyserver being able to communicate over the mobile network with the localproxy on the mobile device; wherein, the proxy server detects a rate ofcontent change at the content source; wherein, the proxy server sets oradjusts timing of keep-alive messages sent to the mobile device based onthe rate of content change.
 2. The system of claim 1, wherein, thetiming includes a time interval value between the keep-alive messagesthat is proportional to the rate of the content change at the contentsource.
 3. The system of claim 1, wherein, the local proxy detects arate of polling requests directed to the content source.
 4. The systemof claim 1, wherein, the timing is determined at least in part by therate of polling requests directed to the content source.
 5. The systemof claim 1, wherein the timing is determined in part based ontime-criticality or time-sensitivity of content provided by the contentsource.
 6. The system of claim 1, wherein the timing is determined inpart based on criticality of an application that is requesting thecontent provided by the content source.
 7. The system of claim 1,wherein indication about the timing is communicated to the mobile devicewith at least some of the keep-alive messages.
 8. The system of claim 1,wherein indication about the timing is communicated to the mobile devicewith a message communicating data.
 9. The system of claim 8, wherein,indication about the timing is communicated to the mobile device with acache-related message including, one or more of, an updated cache entryfor updating a cache entry on the mobile device, and an invalidatingmessage indicating expiration or irrelevance of the cached entry. 10.The system of claim 1, wherein the proxy server sends the keep-alivemessages over SMS when a radio on the mobile device is not activated.11. The system of claim 1, wherein the proxy server sends the keep-alivemessages over a signaling or control channel when a radio on the mobiledevice is not activated.
 12. A method for timing keep-alive messagesused in a wireless network, the method, comprising: monitoring rates ofdata communications between a mobile device and a proxy server; sendinga keep-alive message to the mobile device in response to a decrease inthe rates of data communications between the mobile device and the proxyserver; sending subsequent keep-alive messages to the mobile device atincreasing intervals between the subsequent keep-alive messages todecrease a number of keep-alive messages sent over the wireless network.13. The method of claim 12, further comprising, sending, by the proxyserver, the keep-alive message to the mobile device after communicationwith the mobile device has been dormant for a time period due to thedecrease in the rates of data communications.
 14. The method of claim12, wherein, the rate of communication is determined from a rate ofcontent polls at the mobile device.
 15. The method of claim 12, furthercomprising, detecting a content change rate at which a content at asource changes, wherein, the content at the source is polled by themobile device; wherein, the rate of communication is determined usingthe content change rate.
 16. The method of claim 15, wherein, thecontent change rate is detected by the proxy server.
 17. The method ofclaim 12, wherein, the determining the rate of communication includesdetermining an average rate of communication and a standard deviationfor the average rate.
 18. The method of claim 12, wherein, theincreasing intervals between the subsequent keep-alive messages isdetermined using the average rate of communication and the standarddeviation of the average rate.
 19. The method of claim 12, furthercomprising, indicating to the mobile device that the subsequentkeep-alive messages will be sent at increased intervals to decrease thenumber of keep-alive messages used to signal operational status.
 20. Themethod of claim 19, wherein, the indicating to the mobile device thatthe subsequent keep-alive messages will be sent at increased intervalsincludes sending indications of intervals with one or more of thesubsequent keep-alive messages.
 21. The method of claim 19, wherein, theindicating to the mobile device that the subsequent keep-alive messageswill be sent at increased intervals includes sending indications ofintervals with acknowledgements or responses to content polls.
 22. Themethod of claim 19, further comprising, sending an indication of timingof the subsequent keep-alive messages with a cache-related message. 23.The method of claim 13, wherein, the rate of content polls is determinedfor content polls directed to one resource.
 24. The method of claim 13,wherein, the content polls include polls directed to multiple resourceswith different polling rates; wherein when the keep-alive message issent, is determined using a smallest polling interval among thedifferent polling rates.
 25. A system for distributed management ofperiodic messages used to indicate operational state in a wirelessnetwork, the system, comprising: means for, monitoring rates of datacommunications with a mobile device; means for, sending a periodicmessage to indicate operational state to the mobile device in responseto a decrease in the rates of data communications with the mobiledevice; means for, sending subsequent periodic messages to indicateoperational state to the mobile device at increasing intervals betweenthe subsequent periodic messages to decrease a number of periodicmessages sent over the wireless network; means for, acknowledging to themobile device that the subsequent periodic messages will be sent atincreased intervals.
 26. The system of claim 25, wherein, the mobiledevice has a local cache, wherein, the acknowledging to the mobiledevice regarding the increased intervals occurs in a cache-relatedmessage sent to the mobile device regarding one or more cache entriesstored in the local cache.
 27. The system of claim 26, wherein, thecache-related message includes a cache invalidation message.
 28. Thesystem of claim 25, further comprising, means for, increasing theintervals between the subsequent periodic messages in a multiplicativefashion.
 29. A machine-readable storage medium having stored thereoninstructions which when executed by a processor causes the processor toperform a method for adjusting timing of a keep-alive message, themethod, comprising: determining an initial value for a time intervalbetween keep-alive messages based on a rate of content polls on a mobiledevice; monitoring subsequent rates of communications between the mobiledevice and a proxy server; dynamically adjusting the initial value ofthe time interval to an updated value based on the rate ofcommunication.
 30. The method of claim 29, further comprising, sending,by the proxy server, a keep-alive message to the mobile device aftercommunication with the mobile device has been dormant for a time period;wherein the updated value is user configurable.